Water in our oil, or just alot of hot air?

[[email protected]]

I just watched a program about the huge Oresund bridge between Denmark
and Sweden, and there was a segment about how the corrosion problem for

the bridge was dealt with. Instead of painting, they use sealed
compartments that have the air humidity kept below 60%. This they said
eliminates corrosion. This started me thinking about the corrosion we
aircraft owners are told to guard against, since I have personally been

told by an overhaul shop, that half of all the engines he sees that
need work, need it because of corrosion. There are several "facts" that

I am beginning to question as to their validity. The ones that come to
mind are:

1) You have to get the oil up to 180 deg F or the water in the oil
won't evaporate.


2) Starting and ground running the engine for a minute or so is the
"worst" thing you can possibly do.


3) Flying for an hour will "clean" the oil (or at least evaporate the
water, preventing acid formation) so that it doesn't turn to acid and
dissolve the engine while sitting idle.


There are probably some others, but these three stand out the most

to me. Now I am sure that what I am about to say will not go over well
with some people, but I have the asbestos suit ready and waiting.
My take is that these three "facts" are a bunch of poppycock. Why

or how they got started is anyone's guess, but the reasoning behind
some of them is understandable, for others I wonder what they were
smoking at the time. My thoughts are along these lines, and I admit I
could be wrong, but I don't think so.


Concerning fact #1...Why does someone think that the water has to be
brought to a boil before it will evaporate. Water evaporates very well
even at sub-freezing temperatures,much less at the warm to hot temps
created in a running engine. And at say 140 F, I can't help but believe

that any water or moisture in the engine will be purged quickly. With
water at that temp you can literally see clouds of vapor escaping, and
this is well below boiling. Not that the hotter the engine gets the
water doesn't evaporate more quickly, it does I'm sure. It's just that
in the engine cases which are open to the air at the breather tube and
elsewhere, any heat above say 85 F or so will be more that enough to
dry out the oil in the crankcase. As evidence of this, I ground run my
engine all the time and have for many years. I live in a VERY humid
climate. The oil analysis reports I have done on a regular basis by
Blackstone have never shown any trace of water or moisture. I recently
tore done the engine for rebuild after more then 15 years of perfect
service, and the cam lobes, lifter faces, and every part in the engine
was shiny and totally free from rust or any other corrosion.


Concerning fact #2.... We all constantly clean and oil many of the
things we own such as tools, etc. It is the layer of oil that prevents
the rust. I accept that if the oil is too acidic it could corrode or
"chem mill" the metal, but it takes highly acidic liquid to do that,
and the oils I use have acid buffers in them to deal with mild acidity.



Running is the only way to re-oil all the parts in the engine,
especially the cam and lifters. Just like oiling the machinists tools
that I own keeps them rust free, oiling the engine keeps it rust free I

would think.


Concerning fact #3.... This is the one that really makes me wonder. If
oil needs to be changed every 25-50 hours, how does flying for an hour
clean it? I can't help but think that the longer the oil is used the
dirtier it gets. I guess they think that it's "really" dirty just after

starting, and you "clean" it as you fly.


In closing, it seems to me that many of the things we are told are
contradictory on this subject. I have witnessed many OWT come and go in

my time, so common knowledge isn't always correct. Lean of peak
operation comes to mind. Some blockheads still don't think George Braly

has it right.


Blue Skies
Rusty

[Kyle Boatright]

> wrote in message
oups.com...
>I just watched a program about the huge Oresund bridge between Denmark
> and Sweden, and there was a segment about how the corrosion problem for

Since you made the exact same post to R.A.Owining and RA.Piloting earlier
this week, is there something you're fishing for that didn't come out in
those discussions?

KB

>
> Blue Skies
> Rusty
>

[[email protected]]

Kyle,

If by "earlier in the week" you mean last night when I first posted,
versus this morning after I had done some Sat morning errands and prior
to reading any of the responses, then, no, I wasn't "fishing" for
anything. I was just trying to start a discussion about engine
corrosion that I think needs to be addressed with as many pilots as
possible. Is that all it takes to elict a snide remark from you,
posting the same question to different groups a few hours apart?

Blue skies,
Rusty

[Kyle Boatright]

> wrote in message
oups.com...
> Kyle,
>
> If by "earlier in the week" you mean last night when I first posted,
> versus this morning after I had done some Sat morning errands and prior
> to reading any of the responses, then, no, I wasn't "fishing" for
> anything. I was just trying to start a discussion about engine
> corrosion that I think needs to be addressed with as many pilots as
> possible. Is that all it takes to elict a snide remark from you,
> posting the same question to different groups a few hours apart?
>
> Blue skies,
> Rusty

Not trying to tick you off, just seeking clarification.

KB

[Peter Dohm]

> I just watched a program about the huge Oresund bridge between Denmark
> and Sweden, and there was a segment about how the corrosion problem for
>
> the bridge was dealt with. Instead of painting, they use sealed
> compartments that have the air humidity kept below 60%. This they said
> eliminates corrosion. This started me thinking about the corrosion we
> aircraft owners are told to guard against, since I have personally been
>
> told by an overhaul shop, that half of all the engines he sees that
> need work, need it because of corrosion. There are several "facts" that
>
> I am beginning to question as to their validity. The ones that come to
> mind are:
>
> 1) You have to get the oil up to 180 deg F or the water in the oil
> won't evaporate.
>
>
> 2) Starting and ground running the engine for a minute or so is the
> "worst" thing you can possibly do.
>
>
> 3) Flying for an hour will "clean" the oil (or at least evaporate the
> water, preventing acid formation) so that it doesn't turn to acid and
> dissolve the engine while sitting idle.
>
>
----------------snip-----------
>
> Blue Skies
> Rusty
>
1) In automobiles years ago, the standard assertion was that you had to
get the engine temp up to 160 degrees for the water to evaporate from the
oil. As it happened, that was actually measuring water temp. 160 degrees
was simply the most common coolant thermostat temperature in those days. So
if the same jack asses are still breathing in and out, they are probably
claiming that 205 degrees is mandatory today.
About all I know for sure about water water condensing into much of
anything is:
a) it almost never happens inside a garage or hangar,
b) an engine covered with plastic and sitting on the ground will
accumulate MASSIVE amounts of water,
c) a small light object such as a medicine vial with a snap type lid will
accumulate water outdoors in the shade--such as under a patio roof.
As to evaporation, warmer is faster; but if the ambient humidity is
100%, a surprisingly small temperature rise (10 or 20 degrees IIRC) above
ambient will bring the relative humidity inside the engine below 50%.
2) I am not an aircraft and engine mechanic. However, I am confident
that running a Lycoming engine to circulate the oil is FAR BETTER than
letting it stand; both for the cylinders and the famous cam and tappets.
If I owned it and was not flying at least weekly, you're damned
right I'd ground run it! Not very long, but enough to circulate the oil and
at least get the temp needle off the peg. If, for any reason I was unable
to run the engine frequently, I would certainly place dessicant packages in
the intake(s), exhaust(s), and crankcase breather.
3) Yep, I agree that's an old mechanics tales as well. OTOH, any reason
to fly might bew a good reason.

As to the bridge, apparently the Danes and Sweedes haven't shelled one
another across the straights for so long they've forgotten about that. ;-)
In any case, small amounts of surface rust are trivial for a structure like
a bridge; but seriously debilitating inside an engine!

Peter

[Ernest Christley]

wrote:

> Concerning fact #1...Why does someone think that the water has to be
> brought to a boil before it will evaporate. Water evaporates very well
> even at sub-freezing temperatures,much less at the warm to hot temps
> created in a running engine. And at say 140 F, I can't help but believe
>
> that any water or moisture in the engine will be purged quickly.

Keep in mind where most of the water is coming from, Rusty. Burning gas
produces carbon dioxide and .... WATER. Look at the tailpipes in winter
as you make your morning commute. You'll see water dripping from many
mufflers.

The one hour at 180 degree mark isn't magic. It's just a good point
where you can be sure that the engine has boiled off most of the water
that it collected while warming up. Also keep in mind that the oil is
trying to evaporate the water from an open pan. The engine is mostly
closed up and it has to circulate that oil through several times to get
all the water out (while more is being push back in).

--
This is by far the hardest lesson about freedom. It goes against
instinct, and morality, to just sit back and watch people make
mistakes. We want to help them, which means control them and their
decisions, but in doing so we actually hurt them (and ourselves)."

[Ernest Christley]

Peter Dohm wrote:
> 2) I am not an aircraft and engine mechanic. However, I am confident
> that running a Lycoming engine to circulate the oil is FAR BETTER than
> letting it stand; both for the cylinders and the famous cam and tappets.

You'd be wrong. With a couple minutes running you've just barely got
the thing warmed up (depending on climate). There's a lot of cold metal
in there to begin with. You first start the engine. Fuel burns to
produce CO2 and H20. Lots of it. A lot of that H20 will liquify when it
hits that cold metal, and get swept away into that cold oil. There is
will stay, reacting with other combustion byproducts to form weak
organic acids. They don't eat metal fast, but they do it as long as
they're there.

If you're going to do ground runs, run the engine to circulate HOT oil
for a couple of minutes. You'll be fine then (I think 8*).


--
This is by far the hardest lesson about freedom. It goes against
instinct, and morality, to just sit back and watch people make
mistakes. We want to help them, which means control them and their
decisions, but in doing so we actually hurt them (and ourselves)."

[[email protected]]

Ernest,

I agree with alot of what you said. The point of my OP was not to
challenge what the best care of the engine is. I think we all agree
that flying it an hour a week is what is called for, along with regular
oil changes. What I has me concerned is that many times during the
winter, it is difficult if not impossible to do this. In that
situation, I think it is better to warm up the engine than just let it
sit. The cam and lifter on Lycomings will tolerate no rust at all. Once
you have even a small rust pit in the lifting face of the cam or lifter
I'm afraid you are looking at a tear down in the not too distant
future. Literally beats them to death in short order. And like I said,
my oil analysis results show no water at all, zero. As for the engine
making water, of course it does, and it goes right out the exhaust as
you said. I don't think the engine stays very cold for any length of
time once running. Those babies get hot, and quick, even in the winter.
I doubt if they collect much if any water during start up. I also don't
think the oil turns to an acid capable of dissolving the engine. I
could be wrong, as I haven't done the research, but then, I don't think
anyone else has either. Some say they have, but they aren't showing it
for us to see, at least not that I'm aware of. I realize that the 180
deg is probably meant as a guide, but they do state specifically that
if you don't hit 180, the water won't evaporate. I think this is
nonsense. The oil in a running engine is literally blown and slung
around like a hurricane. It doesn't just sit at the bottom of the sump.
And the volume of oil pumped is huge. 90 psi will do that. I think that
there probably are pockets within the engine that trap water. The front
of the hollow crank comes to mind, but I don't think they ever get
purged of their water, even after hours of operation.

Blue skies,
Rusty

[Chris Wells]

#1 has been circulating for years in motorcycle banter. I've seen for myself that folks who only take short trips on their bikes get white dipsticks, from all the moisture in their oil.



-------------------------------------------------------------------

"Patriotism means to stand by the country. It does not mean to stand by the President."
- President Theodore Roosevelt

[Richard Lamb]

Ernest Christley wrote:

> wrote:
>
> > Concerning fact #1...Why does someone think that the water has to be
> > brought to a boil before it will evaporate. Water evaporates very well
> > even at sub-freezing temperatures,much less at the warm to hot temps
> > created in a running engine. And at say 140 F, I can't help but believe
> > that any water or moisture in the engine will be purged quickly.
>
> Keep in mind where most of the water is coming from, Rusty. Burning gas
> produces carbon dioxide and .... WATER. Look at the tailpipes in winter
> as you make your morning commute. You'll see water dripping from many
> mufflers.
>
> The one hour at 180 degree mark isn't magic. It's just a good point
> where you can be sure that the engine has boiled off most of the water
> that it collected while warming up. Also keep in mind that the oil is
> trying to evaporate the water from an open pan. The engine is mostly
> closed up and it has to circulate that oil through several times to get
> all the water out (while more is being push back in).
>
> --

Water boils off at 212.9 F ?

So operating at 180 oil temp removes water - how?
(Yeah, I know - s l o w l y)

That sounds a lot like "go fly it for an hour".
Obviously the best solution, but not always possible.


On the other hand...



Richard

[Richard Lamb]

Chris Wells wrote:

> #1 has been circulating for years in motorcycle banter. I've seen for
> myself that folks who only take short trips on their bikes get white
> dipsticks, from all the moisture in their oil.
>
> -------------------------------------------------------------------
>
> "Patriotism means to stand by the country. It does not mean to stand by
> the President."
> - President Theodore Roosevelt
>
> --
> Chris Wells

Seen the same on VWs when they only get short ground runs.

The small oil quanity probably exagerates the problem, but it's there
in all reciprocating engines.

As to the hot air aspect, what's in the cylinder after shut down?

If you pull the mixture, the cylinders are cleared with a few blades
of clean (?) air before the prop stops.

Turning off the switch, however, leaves some fuel in the chamber.
One of them is probably under pressure too.

$.02

[Morgans]

"Richard Lamb" > wrote

> Water boils off at 212.9 F ?
>
> So operating at 180 oil temp removes water - how?
> (Yeah, I know - s l o w l y)
>
> That sounds a lot like "go fly it for an hour".
> Obviously the best solution, but not always possible.

I have had it put to me that the 180 is more like an average temperature.
As the oil circulates, it comes into contact with hot parts of the engine,
and until it falls back into the sump, or hits cooler parts of the engine,
it is temporarily well over 212, thus instantly evaporating the water in
that part of the oil.

Sooner or later (in an hour's time) all of the oil has passed over the hot
parts, and all the water is magically gone! <g>
--
Jim in NC

[Roger]

On Sun, 23 Apr 2006 00:24:07 -0400, "Peter Dohm"
> wrote:

>> I just watched a program about the huge Oresund bridge between Denmark
>> and Sweden, and there was a segment about how the corrosion problem for
>>
>> the bridge was dealt with. Instead of painting, they use sealed
>> compartments that have the air humidity kept below 60%. This they said
>> eliminates corrosion. This started me thinking about the corrosion we
>> aircraft owners are told to guard against, since I have personally been
>>
>> told by an overhaul shop, that half of all the engines he sees that
>> need work, need it because of corrosion. There are several "facts" that
>>
>> I am beginning to question as to their validity. The ones that come to
>> mind are:
>>
>> 1) You have to get the oil up to 180 deg F or the water in the oil
>> won't evaporate.
>>
>>
>> 2) Starting and ground running the engine for a minute or so is the
>> "worst" thing you can possibly do.
>>
>>
>> 3) Flying for an hour will "clean" the oil (or at least evaporate the
>> water, preventing acid formation) so that it doesn't turn to acid and
>> dissolve the engine while sitting idle.
>>
>>
>----------------snip-----------
>>
>> Blue Skies
>> Rusty
>>
>1) In automobiles years ago, the standard assertion was that you had to
>get the engine temp up to 160 degrees for the water to evaporate from the
>oil. As it happened, that was actually measuring water temp. 160 degrees
>was simply the most common coolant thermostat temperature in those days. So
>if the same jack asses are still breathing in and out, they are probably
>claiming that 205 degrees is mandatory today.
> About all I know for sure about water water condensing into much of
>anything is:
>a) it almost never happens inside a garage or hangar,

We must live in different climates.
Here in Central Michigan it's not unusual to find the airplane
"dripping" wet with temperature changes.

I have an garage attached to the house. It's not unusual to find the
cars sweating with temperature and humidity changes. I had to work on
the garden tractor today and the engine is wet from the humidity and
temperature changes. (It's been 100% since last night and rained most
of the day.

Current temp is 50F) The weather for the area says 85% but it's
raining with light fog. Of course the briefing I printed out at 3:00
AM says visibility >6, 5000 sct, 10,000 bkn with temp 4 in light rain
and thunderstorms with 5,000 sct.
It's now starting to clear from the west and MOP is showing Vis 10,
1000 sct, 1500 bkn. Most of the afternoon was >1 and >500.

>b) an engine covered with plastic and sitting on the ground will
>accumulate MASSIVE amounts of water,

We get the same thing in our hangars on the airplanes and engines.
If I went out to the hangar today I'd find the plane dripping. The
temp is dropping slowly. It'll be near the upper 30's tonight.
Opening the cowl would find water droplets on the cylinders and
crankcase.

This is in a well ventilated metal hangar with a concrete floor.

>c) a small light object such as a medicine vial with a snap type lid will
>accumulate water outdoors in the shade--such as under a patio roof.
> As to evaporation, warmer is faster; but if the ambient humidity is
>100%, a surprisingly small temperature rise (10 or 20 degrees IIRC) above
>ambient will bring the relative humidity inside the engine below 50%.

Also the engine breathes in and out with temperature changes. So
cooling not only raised the relative humidity inside, it brings in
more cool, damp air.

>2) I am not an aircraft and engine mechanic. However, I am confident
>that running a Lycoming engine to circulate the oil is FAR BETTER than
>letting it stand; both for the cylinders and the famous cam and tappets.

If it's going to set long it needs to be protected not ground run
according to the engine manufacturers literature.

> If I owned it and was not flying at least weekly, you're damned
>right I'd ground run it! Not very long, but enough to circulate the oil and

If you are going to ground run it you want to bring it up to operating
temp. It's the short runs that not only don't evaporate much of
anything they put a lot more *stuff* into the oil as the cold engine
isn't running as efficient as a warm one and the byproducts can
condense inside.

Find a good clean spot on the ramp, let the engine warm up normally.
Then stand on the brakes and wind 'er up for a prolonged run. Of
course then makes the neighbors unhappy.

>at least get the temp needle off the peg. If, for any reason I was unable
>to run the engine frequently, I would certainly place dessicant packages in
>the intake(s), exhaust(s), and crankcase breather.

They usually put desiccants in the plugs and plug off the intake,
exhaust and breathers.

Go into Pioneer Airport and look at the antiques that have the engines
preserved. I've forgotten the term, but at any rate each prop has a
note on it that says "Do not turn prop. Engine has been preserved".

>3) Yep, I agree that's an old mechanics tales as well. OTOH, any reason
>to fly might bew a good reason.

Might be but both Lycombing and Continental subscribe to it.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
>
>As to the bridge, apparently the Danes and Sweedes haven't shelled one
>another across the straights for so long they've forgotten about that. ;-)
>In any case, small amounts of surface rust are trivial for a structure like
>a bridge; but seriously debilitating inside an engine!
>
>Peter
>

[Roger]

On 23 Apr 2006 02:18:53 -0700, wrote:

>Ernest,
>
> I agree with alot of what you said. The point of my OP was not to
>challenge what the best care of the engine is. I think we all agree
>that flying it an hour a week is what is called for, along with regular
>oil changes. What I has me concerned is that many times during the
>winter, it is difficult if not impossible to do this. In that

Get a good engine block and cylinder head heater. Wrap up the entire
cowl with plenty of good thermal blankets and use an engine heater to
keep the oil dry.

>situation, I think it is better to warm up the engine than just let it
>sit. The cam and lifter on Lycomings will tolerate no rust at all. Once
>you have even a small rust pit in the lifting face of the cam or lifter
>I'm afraid you are looking at a tear down in the not too distant
>future. Literally beats them to death in short order. And like I said,
>my oil analysis results show no water at all, zero. As for the engine
>making water, of course it does, and it goes right out the exhaust as
>you said. I don't think the engine stays very cold for any length of
>time once running. Those babies get hot, and quick, even in the winter.
>I doubt if they collect much if any water during start up. I also don't
>think the oil turns to an acid capable of dissolving the engine. I

Again we disagree. If I don't use the engine heater the oil will be
almost milky within the first five hours. Using the heater it's still
clear to around the 20 hour mark. OTOH my engine has no oil filter so
the oil changes come at 25 hours. In 25 hours the oil doesn't go down
enough to hardly see on the dip stick, so it's using less than a pint
in 25 hours and is almost at TBO. BTW it has a wet vacuum pump.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

>could be wrong, as I haven't done the research, but then, I don't think
>anyone else has either. Some say they have, but they aren't showing it
>for us to see, at least not that I'm aware of. I realize that the 180
>deg is probably meant as a guide, but they do state specifically that
>if you don't hit 180, the water won't evaporate. I think this is
>nonsense. The oil in a running engine is literally blown and slung
>around like a hurricane. It doesn't just sit at the bottom of the sump.
>And the volume of oil pumped is huge. 90 psi will do that. I think that
>there probably are pockets within the engine that trap water. The front
>of the hollow crank comes to mind, but I don't think they ever get
>purged of their water, even after hours of operation.
>
>Blue skies,
>Rusty

[Morgans]

"Roger" > wrote

> We must live in different climates.
> Here in Central Michigan it's not unusual to find the airplane
> "dripping" wet with temperature changes.
>
> I have an garage attached to the house. It's not unusual to find the
> cars sweating with temperature and humidity changes. I had to work on
> the garden tractor today and the engine is wet from the humidity and
> temperature changes. (It's been 100% since last night and rained most
> of the day.

I feel your pain! <g>

NC is like that, at times, also.

Want a good piece of advise? Insulate your garage, put up good insulated
garage doors, and with good seals installed. Run one 8" duct into the
garage from your central heat and air. It makes a huge difference at not
all that much expense.
--
Jim in NC

[Peter Dohm]

"Morgans" > wrote in message
...
>
> "Roger" > wrote
>
> > We must live in different climates.
> > Here in Central Michigan it's not unusual to find the airplane
> > "dripping" wet with temperature changes.
> >
> > I have an garage attached to the house. It's not unusual to find the
> > cars sweating with temperature and humidity changes. I had to work on
> > the garden tractor today and the engine is wet from the humidity and
> > temperature changes. (It's been 100% since last night and rained most
> > of the day.
>
> I feel your pain! <g>
>
> NC is like that, at times, also.
>
> Want a good piece of advise? Insulate your garage, put up good insulated
> garage doors, and with good seals installed. Run one 8" duct into the
> garage from your central heat and air. It makes a huge difference at not
> all that much expense.
> --
> Jim in NC
>
I am currently in Florida. However, I'll keep your solution in mind in case
of a move to a cooler climate.

Thanks for the advice.
Peter

[clare at snyder.on.ca]

On Sun, 23 Apr 2006 18:36:42 -0400, Roger
> wrote:

>On Sun, 23 Apr 2006 00:24:07 -0400, "Peter Dohm"
> wrote:
>
>>> I just watched a program about the huge Oresund bridge between Denmark
>>> and Sweden, and there was a segment about how the corrosion problem for
>>>
>>> the bridge was dealt with. Instead of painting, they use sealed
>>> compartments that have the air humidity kept below 60%. This they said
>>> eliminates corrosion. This started me thinking about the corrosion we
>>> aircraft owners are told to guard against, since I have personally been
>>>
>>> told by an overhaul shop, that half of all the engines he sees that
>>> need work, need it because of corrosion. There are several "facts" that
>>>
>>> I am beginning to question as to their validity. The ones that come to
>>> mind are:
>>>
>>> 1) You have to get the oil up to 180 deg F or the water in the oil
>>> won't evaporate.
>>>
>>>
>>> 2) Starting and ground running the engine for a minute or so is the
>>> "worst" thing you can possibly do.
>>>
>>>
>>> 3) Flying for an hour will "clean" the oil (or at least evaporate the
>>> water, preventing acid formation) so that it doesn't turn to acid and
>>> dissolve the engine while sitting idle.
>>>
>>>
>>----------------snip-----------
>>>
>>> Blue Skies
>>> Rusty
>>>
>>1) In automobiles years ago, the standard assertion was that you had to
>>get the engine temp up to 160 degrees for the water to evaporate from the
>>oil. As it happened, that was actually measuring water temp. 160 degrees
>>was simply the most common coolant thermostat temperature in those days. So
>>if the same jack asses are still breathing in and out, they are probably
>>claiming that 205 degrees is mandatory today.
>> About all I know for sure about water water condensing into much of
>>anything is:
>>a) it almost never happens inside a garage or hangar,
>
>We must live in different climates.
>Here in Central Michigan it's not unusual to find the airplane
>"dripping" wet with temperature changes.
>
>I have an garage attached to the house. It's not unusual to find the
>cars sweating with temperature and humidity changes. I had to work on
>the garden tractor today and the engine is wet from the humidity and
>temperature changes. (It's been 100% since last night and rained most
>of the day.
>
>Current temp is 50F) The weather for the area says 85% but it's
>raining with light fog. Of course the briefing I printed out at 3:00
>AM says visibility >6, 5000 sct, 10,000 bkn with temp 4 in light rain
>and thunderstorms with 5,000 sct.
>It's now starting to clear from the west and MOP is showing Vis 10,
>1000 sct, 1500 bkn. Most of the afternoon was >1 and >500.
>
>>b) an engine covered with plastic and sitting on the ground will
>>accumulate MASSIVE amounts of water,
>
>We get the same thing in our hangars on the airplanes and engines.
>If I went out to the hangar today I'd find the plane dripping. The
>temp is dropping slowly. It'll be near the upper 30's tonight.
>Opening the cowl would find water droplets on the cylinders and
>crankcase.
>
>This is in a well ventilated metal hangar with a concrete floor.
>
>>c) a small light object such as a medicine vial with a snap type lid will
>>accumulate water outdoors in the shade--such as under a patio roof.
>> As to evaporation, warmer is faster; but if the ambient humidity is
>>100%, a surprisingly small temperature rise (10 or 20 degrees IIRC) above
>>ambient will bring the relative humidity inside the engine below 50%.
>
>Also the engine breathes in and out with temperature changes. So
>cooling not only raised the relative humidity inside, it brings in
>more cool, damp air.
>
>>2) I am not an aircraft and engine mechanic. However, I am confident
>>that running a Lycoming engine to circulate the oil is FAR BETTER than
>>letting it stand; both for the cylinders and the famous cam and tappets.
>
>If it's going to set long it needs to be protected not ground run
>according to the engine manufacturers literature.
>
>> If I owned it and was not flying at least weekly, you're damned
>>right I'd ground run it! Not very long, but enough to circulate the oil and
>
>If you are going to ground run it you want to bring it up to operating
>temp. It's the short runs that not only don't evaporate much of
>anything they put a lot more *stuff* into the oil as the cold engine
>isn't running as efficient as a warm one and the byproducts can
>condense inside.
>
>Find a good clean spot on the ramp, let the engine warm up normally.
>Then stand on the brakes and wind 'er up for a prolonged run. Of
>course then makes the neighbors unhappy.
>
>>at least get the temp needle off the peg. If, for any reason I was unable
>>to run the engine frequently, I would certainly place dessicant packages in
>>the intake(s), exhaust(s), and crankcase breather.
>
>They usually put desiccants in the plugs and plug off the intake,
>exhaust and breathers.
>
>Go into Pioneer Airport and look at the antiques that have the engines
>preserved. I've forgotten the term, but at any rate each prop has a
>note on it that says "Do not turn prop. Engine has been preserved".
>
>>3) Yep, I agree that's an old mechanics tales as well. OTOH, any reason
>>to fly might bew a good reason.
>
>Might be but both Lycombing and Continental subscribe to it.
>
>Roger Halstead (K8RI & ARRL life member)
>(N833R, S# CD-2 Worlds oldest Debonair)
>www.rogerhalstead.com
>>
>>As to the bridge, apparently the Danes and Sweedes haven't shelled one
>>another across the straights for so long they've forgotten about that. ;-)
>>In any case, small amounts of surface rust are trivial for a structure like
>>a bridge; but seriously debilitating inside an engine!
>>
>>Peter
>>
If you feel the need to get the oil moving in a stored engine, crank
it over with the fuel and mags shut off untill full oil pressure is
acheived, then recharge the battery. Do NOT ground run for short
periods without getting the oil temperature up to dry it out.
Particularly important with top-cam engines, as the cams and tappets
are very prone to condensation induced corrosion failures. And worse
with Synthetic oils than standard petro oils.
*** Posted via a free Usenet account from http://www.teranews.com ***

[J.Kahn]

wrote:
> Ernest,
>
> I agree with alot of what you said. The point of my OP was not to
> challenge what the best care of the engine is. I think we all agree
> that flying it an hour a week is what is called for, along with regular
> oil changes. What I has me concerned is that many times during the
> winter, it is difficult if not impossible to do this. In that
> situation, I think it is better to warm up the engine than just let it
> sit. The cam and lifter on Lycomings will tolerate no rust at all. Once
> you have even a small rust pit in the lifting face of the cam or lifter
> I'm afraid you are looking at a tear down in the not too distant
> future. Literally beats them to death in short order. And like I said,
> my oil analysis results show no water at all, zero. As for the engine
> making water, of course it does, and it goes right out the exhaust as
> you said. I don't think the engine stays very cold for any length of
> time once running. Those babies get hot, and quick, even in the winter.
> I doubt if they collect much if any water during start up. I also don't
> think the oil turns to an acid capable of dissolving the engine. I
> could be wrong, as I haven't done the research, but then, I don't think
> anyone else has either. Some say they have, but they aren't showing it
> for us to see, at least not that I'm aware of. I realize that the 180
> deg is probably meant as a guide, but they do state specifically that
> if you don't hit 180, the water won't evaporate. I think this is
> nonsense. The oil in a running engine is literally blown and slung
> around like a hurricane. It doesn't just sit at the bottom of the sump.
> And the volume of oil pumped is huge. 90 psi will do that. I think that
> there probably are pockets within the engine that trap water. The front
> of the hollow crank comes to mind, but I don't think they ever get
> purged of their water, even after hours of operation.
>
> Blue skies,
> Rusty
>
You don't really need to fly it once a week. Once a month will do as
long as it gets an hour or so. I bought a '68 Cardinal in '89 that had
never even had a cylinder removed since new (original unbroken Lycoming
duck egg blue paint at the cylinder bases). I went back through the
logs and found that while it only had 1100 hours in 21 years, it had
never gone more than a 40 day period without flying in all that time.

I sold it to a guy in '93 who still owns it, keeps it outside and it
STILL have never even had a cylinder removed. He only puts about 20 or
30 hours a year on it but makes sure it never sits more than a month.

The vast majority of private aircraft that need tops after 1000 hrs
often go 3 to 6 months at a time without flying.

John

[Montblack]

("Roger" wrote)
> Go into Pioneer Airport and look at the antiques that have the engines
> preserved. I've forgotten the term, but at any rate each prop has a note
> on it that says "Do not turn prop. Engine has been preserved".


Pickled? Fogged?


Montblack

[Richard Lamb]

Morgans wrote:

> "Roger" > wrote
>
> > We must live in different climates.
> > Here in Central Michigan it's not unusual to find the airplane
> > "dripping" wet with temperature changes.
> >
> > I have an garage attached to the house. It's not unusual to find the
> > cars sweating with temperature and humidity changes. I had to work on
> > the garden tractor today and the engine is wet from the humidity and
> > temperature changes. (It's been 100% since last night and rained most
> > of the day.
>
> I feel your pain! <g>
>
> NC is like that, at times, also.
>
> Want a good piece of advise? Insulate your garage, put up good insulated
> garage doors, and with good seals installed. Run one 8" duct into the
> garage from your central heat and air. It makes a huge difference at not
> all that much expense.
> --
> Jim in NC

That's good advice...

[Roger]

On Sun, 23 Apr 2006 19:40:10 -0400, "Morgans"
> wrote:

>
>"Roger" > wrote
>
>> We must live in different climates.
>> Here in Central Michigan it's not unusual to find the airplane
>> "dripping" wet with temperature changes.
>>
>> I have an garage attached to the house. It's not unusual to find the
>> cars sweating with temperature and humidity changes. I had to work on
>> the garden tractor today and the engine is wet from the humidity and
>> temperature changes. (It's been 100% since last night and rained most
>> of the day.
>
>I feel your pain! <g>
>
>NC is like that, at times, also.

Winters are getting a bit warmer, (5 weeks shorter in the last 50
years according to the State of Michigan DNR) and more humidity. That
means we spend more of the year in the 30 to 50 degree range with high
humidity.

>
>Want a good piece of advise? Insulate your garage, put up good insulated
>garage doors, and with good seals installed. Run one 8" duct into the

It's already insulated with insulated doors, but I need to add the air
duct.

I'm glad you mentioned that as the duct ends within two feet of the
garage wall. All I need is to add a shutter/valve to the duct, cut a
hole through the 2 X 10 and install a register. It'd probably be a
lot better if I carried it up the wall and over to the center of the
garage, but being lazy I'll be lucky to get it into the garage. Great
idea though.

>garage from your central heat and air. It makes a huge difference at not
>all that much expense.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

[Stealth Pilot]

On Mon, 24 Apr 2006 00:47:38 -0400, Roger
> wrote:

>On Sun, 23 Apr 2006 19:40:10 -0400, "Morgans"
> wrote:

>>Want a good piece of advise? Insulate your garage, put up good insulated
>>garage doors, and with good seals installed. Run one 8" duct into the
>
>It's already insulated with insulated doors, but I need to add the air
>duct.
>
>I'm glad you mentioned that as the duct ends within two feet of the
>garage wall. All I need is to add a shutter/valve to the duct, cut a
>hole through the 2 X 10 and install a register. It'd probably be a
>lot better if I carried it up the wall and over to the center of the
>garage, but being lazy I'll be lucky to get it into the garage. Great
>idea though.
>
>>garage from your central heat and air. It makes a huge difference at not
>>all that much expense.
>

roger site the vent so that it ducts on to the floor and try for
coanda effect to take the blast into the centre area.
I'm sure it can work.

Stealth Pilot

[Stealth Pilot]

On Sun, 23 Apr 2006 22:45:06 -0400, "J.Kahn"
> wrote:


>>
>You don't really need to fly it once a week. Once a month will do as
>long as it gets an hour or so.

an hour or two *after* the engine temperature is at the normal running
temp range will see it right.

white oil? fill it up with avgas and fly out the tank in one
uninterrupted flight and it should be black again.

my aircraft occasionally sits for longer than I want and I find on a
long cross country that by the end of the second day's flying it is
running like a well oiled sewing machine again. flying for shorter
periods never seems to get the sewing machine effect where it runs
noticeably sweeter.

Stealth Pilot

[Peter Dohm]

"Montblack" > wrote in message
...
> ("Roger" wrote)
> > Go into Pioneer Airport and look at the antiques that have the engines
> > preserved. I've forgotten the term, but at any rate each prop has a
note
> > on it that says "Do not turn prop. Engine has been preserved".
>
>
> Pickled? Fogged?
>
>
> Montblack
>
I never personallhy heard of Fogged, but I know that Pickled was a common
term.

Peter

[[email protected]]

>And like I said,
>my oil analysis results show no water at all, zero. As for the engine
>making water, of course it does, and it goes right out the exhaust as
>you said.

Most of it goes out the exhaust. Some of it squeezes past the rings,
since everything is still cool and the gaps are larger, and it
condenses in the crankcase. It does it to a lesser degree once it's
warmed up.

>I don't think the engine stays very cold for any length of
>time once running. Those babies get hot, and quick, even in the winter.

Only if your idea of winter is around 40 F. Many of us live in
climates that get much colder than that. We have airplanes here that
never see over 150 F on the oil temp in winter, and seldom more than
300 on the CHT.

>I doubt if they collect much if any water during start up.

> I've taken the rocker covers off a brand-new engine after it's been ground run for five minutes, and they're full of water. If I take them off after it has 200 hours on it, they're rusty.

>I also don't
>think the oil turns to an acid capable of dissolving the engine.

You just haven't seen it, so you don't believe it.

>I could be wrong, as I haven't done the research, but then, I don't think
>anyone else has either.

More "show me." Lycoming and Continental and the people who make engine
oils HAVE done the research and published it. Many more, who aren't
trying to sell oil or additives or engines, have done it as well.

>Some say they have, but they aren't showing it
>for us to see, at least not that I'm aware of. I realize that the 180
>deg is probably meant as a guide, but they do state specifically that
>if you don't hit 180, the water won't evaporate.

Water's vapor pressure rises with temperature, if you remember your
physics. Raising the vapor pressure drives it of sooner. It doesn't
have to boil. 180 is a recommendation. Below that, the water might form
in the case faster than it will evaporate, and you'll have increasing
amounts accumulating in the engine.

The research is there. Here are some who have experience in the
area:
http://www.sacskyranch.com/corrosion.htm

http://doc.tms.org/ezMerchant/prodtms.nsf/ProductLookupItemID/JOM-0505-54/$FILE/JOM-0505-54F.pdf?OpenElement

http://www.ramaircraft.com/Maintenance-Tips/Oil-Recommendations.htm

http://www.memagazine.org/backissues/may99/features/vitalsigns/vitalsigns.html

Lots more if you Google it.

Dan

[Peter Dohm]

-----------------snip---------------
> >If you are going to ground run it you want to bring it up to operating
> >temp. It's the short runs that not only don't evaporate much of
> >anything they put a lot more *stuff* into the oil as the cold engine
> >isn't running as efficient as a warm one and the byproducts can
> >condense inside.
> >
> >Find a good clean spot on the ramp, let the engine warm up normally.
> >Then stand on the brakes and wind 'er up for a prolonged run. Of
> >course then makes the neighbors unhappy.
> >
> >>at least get the temp needle off the peg. If, for any reason I was
unable
> >>to run the engine frequently, I would certainly place dessicant packages
in
> >>the intake(s), exhaust(s), and crankcase breather.
> >
---------------snip-------------------
> If you feel the need to get the oil moving in a stored engine, crank
> it over with the fuel and mags shut off untill full oil pressure is
> acheived, then recharge the battery. Do NOT ground run for short
> periods without getting the oil temperature up to dry it out.
> Particularly important with top-cam engines, as the cams and tappets
> are very prone to condensation induced corrosion failures. And worse
> with Synthetic oils than standard petro oils.

The top cam engines are exactly the problem, which is why I really think we
are going around in a circle. And we are not the first to do so, nor will
we be the last.

In my admittedly limited understanding of top cam engines, the lobes and
tappets are essentially "splash lubricated" in that their coating of oil is
primarily by oil thrown from the crankshaft. In the case of Lycoming
engines, I presume that the intake lobes would receive some oil that could
travel from the camshaft bearings; but I am not convinced that the exhaust
lobes would receive any lubrication at cranking speeds.

Admittedly, there are direct spray modifications available for the Lycoming
cam lobes--according to a bonafide Lycoming Bigot in my chapter who has no
intention of ever flying his airplane at night or under IFR. However, I
have no adea whether the modification is certified under 14 CFR part 33. In
the case of Experimental Category and Day VFR only, presuming that the
modification was part of the original construction, the problem is solved:
just turn off the fuel, crank the engine, and recharge the battery. If the
aircraft is certified under 14 CFR part 23, or if IFR or Night VFR is
included, then my reading of AC 23-11A suggests that the engine as currently
installed is expected be certified and airworthy under 14 CFR part 33 and
the propelled as installed is expected to be certified and airworthy under
14 CFR part 35.

If we simply knew on the last day of good flying weather that it was time to
pickle the engine for the off season, the solution would be pretty simple.
However, other posts in the thread have elaborated that this is not
necessarily the case, and in fact the issue of preserving the engine is
likely to come up at the least opportune time. I admit that part of the
foregoing point escaped my attention as well, and I stand corrected.
Engines do breath in and out with changes in both temperature and barometric
pressure, and a ground run in the rain was really not a recommendation.

Peter

Disclaimer: this is not my occupational specialty and I don't recall why I
happened to read AC 23-11A. Also, if your airplane is registered outside
the US, different rules apply. Also, this is entirely redundant as you
already know by reading the thread; however everyone should go back and read
it again.
Alternate Manager of Duplication
The Depeartment of Redundancy Department

[Montblack]

("Peter Dohm" wrote)
>> Pickled? Fogged?

> I never personallhy heard of Fogged, but I know that Pickled was a common
> term.


Fogging oil for "winterizing" an engine. Spray it in the spark plug holes.

http://www.pennzoil.com/products/marine/fogging_oil.html

http://www.seafoamsales.com/deepCreepTech.htm
DEEP CREEP Engine Fogging - scroll to the middle


Montblack

[[email protected]]

>Admittedly, there are direct spray modifications >available for the Lycoming
>cam lobes--according to a bonafide Lycoming Bigot in >my chapter

We're buying three Lyc Factory overhauls this spring (O-320) and the
dealer tells me that Lycoming has come up with a roller tappet and cam
to match. The case is different, to make room for the extra machinery.
It's an option right now, apparently. I imagine they'll try to convert
the fleet. The roller tappet is likely in response to scuffing issues.
We haven't had any problem with scuff for years, since we started using
an oil with the additive Lycoming recommends (Aeroshell 15W50).

Dan

[Peter Dohm]

"Montblack" > wrote in message
...
> ("Peter Dohm" wrote)
> >> Pickled? Fogged?
>
> > I never personallhy heard of Fogged, but I know that Pickled was a
common
> > term.
>
>
> Fogging oil for "winterizing" an engine. Spray it in the spark plug holes.
>
> http://www.pennzoil.com/products/marine/fogging_oil.html
>
> http://www.seafoamsales.com/deepCreepTech.htm
> DEEP CREEP Engine Fogging - scroll to the middle
>
>
> Montblack
>

Hmmm. That could work, especially if you can get it to the cam lobes as
well.

Peter

[Peter Dohm]

> >Admittedly, there are direct spray modifications >available for the
Lycoming
> >cam lobes--according to a bonafide Lycoming Bigot in >my chapter
>
> We're buying three Lyc Factory overhauls this spring (O-320) and the
> dealer tells me that Lycoming has come up with a roller tappet and cam
> to match. The case is different, to make room for the extra machinery.
> It's an option right now, apparently. I imagine they'll try to convert
> the fleet. The roller tappet is likely in response to scuffing issues.
> We haven't had any problem with scuff for years, since we started using
> an oil with the additive Lycoming recommends (Aeroshell 15W50).
>
> Dan
>
I've thought for some time that roller tappets would be the real solution,
and I am glad to hear that they will be offered for the O-320.

If you're buying three, your equipment probably dosn't have excessive
periods of inactivity. It's also good to hear that the recommended oil
additive has resolved any residual scuffing problems up until now.

Peter

[[email protected]]

Peter Dohm wrote:

>
> If you're buying three, your equipment probably dosn't have excessive
> periods of inactivity. It's also good to hear that the recommended oil
> additive has resolved any residual scuffing problems up until now.
>
> Peter

They fly a lot, and that's what makes them last well. But we
still find water in the rocker covers after just a runup of about 10
minutes before inspection, even in summer weather. It's not there if
the airplane comes in after a flight, unless the weather was really
cold. We'll also often see water droplets on the oil dipstick.
On the other hand, in my old A-65 in my Jodel, I see corrosion
simply because it doesn't get flown much and when it does it's for
rather short flights. Too busy working on airplanes or with students to
find much time to play.

Dan

[Highflyer]

> wrote in message
oups.com...
>I just watched a program about the huge Oresund bridge between Denmark
> and Sweden, and there was a segment about how the corrosion problem for
>
> the bridge was dealt with. Instead of painting, they use sealed
> compartments that have the air humidity kept below 60%. This they said
> eliminates corrosion. This started me thinking about the corrosion we
> aircraft owners are told to guard against, since I have personally been
>
> told by an overhaul shop, that half of all the engines he sees that
> need work, need it because of corrosion. There are several "facts" that
>
> I am beginning to question as to their validity. The ones that come to
> mind are:
>
> 1) You have to get the oil up to 180 deg F or the water in the oil
> won't evaporate.

The water in the oil will obviously evaporate at lower temperatures.
However, when you run the engine it puts combustion byproducts into the
crankcase. ( There is always a bit gets by those rather sloppy piston
rings. ) These byproducts are the oxidized or "burned" results of burning a
hydrocarbon fuel. Burnt hydrogen is H2O or water. Burnt carbon is CO or
CO2. These wind up in your oil as a result of running the engine. The
trick is to get the oil warm enough so that they evaporate away FASTER than
you add them into the mixture. Then you will get the water out of the oil
and avoid the formation of the organic acids that will cause corrosion
inside the engine. Minor surface corrosion that is irrelevant on the
outside of the engine may be much more serious on the inside. Yes, I have
overhauled more engines because of corrosion than because of wear.

Running the engine for a few minutes on the ground will add to the water and
other corrosives in the oil. Then you turn it off and let it work on the
guts of your engine. Do that if you want. I do overhauls quite
reasonably.

Running the engine for a longer time until the oil is warm enough to
evaporate off the water on the ground? That is not so good either. By the
time the oil is warm from ground running with most aircraft engines the
cylinder head temps are going off scale and you are beginning to cause other
problems from overheating. Look at all the guys shutting down from
overheating while waiting in line for takeoff at Oshkosh after the airshow!
:-)

If you go ahead and go flying, at least a little bit, you both warn and
distribute the oil and cool the engine. Why not go flying anyway. Isn't
that what you have the airplane for? :-)


>
>
> 2) Starting and ground running the engine for a minute or so is the
> "worst" thing you can possibly do.
>
See above.

>
> 3) Flying for an hour will "clean" the oil (or at least evaporate the
> water, preventing acid formation) so that it doesn't turn to acid and
> dissolve the engine while sitting idle.
>
See above.

>
> There are probably some others, but these three stand out the most
>
> to me. Now I am sure that what I am about to say will not go over well
> with some people, but I have the asbestos suit ready and waiting.
> My take is that these three "facts" are a bunch of poppycock. Why
>
> or how they got started is anyone's guess, but the reasoning behind
> some of them is understandable, for others I wonder what they were
> smoking at the time. My thoughts are along these lines, and I admit I
> could be wrong, but I don't think so.
>

You are wrong. Sorry.

>
> Concerning fact #1...Why does someone think that the water has to be
> brought to a boil before it will evaporate. Water evaporates very well
> even at sub-freezing temperatures,much less at the warm to hot temps
> created in a running engine. And at say 140 F, I can't help but believe
>
> that any water or moisture in the engine will be purged quickly. With
> water at that temp you can literally see clouds of vapor escaping, and
> this is well below boiling. Not that the hotter the engine gets the
> water doesn't evaporate more quickly, it does I'm sure. It's just that
> in the engine cases which are open to the air at the breather tube and
> elsewhere, any heat above say 85 F or so will be more that enough to
> dry out the oil in the crankcase. As evidence of this, I ground run my
> engine all the time and have for many years. I live in a VERY humid
> climate. The oil analysis reports I have done on a regular basis by
> Blackstone have never shown any trace of water or moisture. I recently
> tore done the engine for rebuild after more then 15 years of perfect
> service, and the cam lobes, lifter faces, and every part in the engine
> was shiny and totally free from rust or any other corrosion.
>

See above. Lucky lucky.

>
> Concerning fact #2.... We all constantly clean and oil many of the
> things we own such as tools, etc. It is the layer of oil that prevents
> the rust. I accept that if the oil is too acidic it could corrode or
> "chem mill" the metal, but it takes highly acidic liquid to do that,
> and the oils I use have acid buffers in them to deal with mild acidity.
>
>
>
> Running is the only way to re-oil all the parts in the engine,
> especially the cam and lifters. Just like oiling the machinists tools
> that I own keeps them rust free, oiling the engine keeps it rust free I
>
> would think.

Quite true. See above.
>
>
> Concerning fact #3.... This is the one that really makes me wonder. If
> oil needs to be changed every 25-50 hours, how does flying for an hour
> clean it? I can't help but think that the longer the oil is used the
> dirtier it gets. I guess they think that it's "really" dirty just after
>
> starting, and you "clean" it as you fly.

Clearly you don't understand the difference between dirty oil and wet oil.
Just as combustion puts gobs of water into the oil, it also puts in some
soot, making the oil eventually turn black. Detergent oils also pick up
sludge and crud from within the engine and carry it around in suspension in
the oil. Good idea to dump it out and get a fresh start every once in a
while.
I recommend 25 hours without a filter and 50 hours with a filter.
Remember, oil is much cheaper than engines! :-)

>
>
> In closing, it seems to me that many of the things we are told are
> contradictory on this subject. I have witnessed many OWT come and go in
>
> my time, so common knowledge isn't always correct. Lean of peak
> operation comes to mind. Some blockheads still don't think George Braly
>
> has it right.
>

And some blockheads fly in the face of experience and proven test results.
Everything we know is NOT an OWT. Most OWT's are coming from people who
only THINK they know but have no scientific data to support their possibly
erroneous observation.

For example:

Cigarette smokers often get lung cancer.

Cigar smokers sometimes get lung cancer.

Pipe smokers rarely get lung cancer.

Cigarette smokers often use cigarette lighters.

Cigar smokers sometimes use cigarette lighters.

Pipe smokers usually use matches and rarely use cigarette lighters.

All smoke tobacco products.

Clearly the correlation with lung cancer is with cigarette lighters, and not
with tobacco products.

If we all used matches instead of cigarette lighters no one would get lung
cancer any more!

I love logic.

My kid brother was a statistician for the Navy before he retired. He had a
lovely comment about statistics.

"Most people use statistics like a drunk uses a lamp post. For support
instead of illumination!"

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )


>
> Blue Skies
> Rusty
>

[Highflyer]

"Peter Dohm" > wrote in message
. ..
> "Morgans" > wrote in message
> ...
>>
>> "Roger" > wrote
>>
>> > We must live in different climates.
>> > Here in Central Michigan it's not unusual to find the airplane
>> > "dripping" wet with temperature changes.
>> >
>> > I have an garage attached to the house. It's not unusual to find the
>> > cars sweating with temperature and humidity changes. I had to work on
>> > the garden tractor today and the engine is wet from the humidity and
>> > temperature changes. (It's been 100% since last night and rained most
>> > of the day.
>>
>> I feel your pain! <g>
>>
>> NC is like that, at times, also.
>>
>> Want a good piece of advise? Insulate your garage, put up good insulated
>> garage doors, and with good seals installed. Run one 8" duct into the
>> garage from your central heat and air. It makes a huge difference at not
>> all that much expense.
>> --
>> Jim in NC
>>
> I am currently in Florida. However, I'll keep your solution in mind in
> case
> of a move to a cooler climate.
>
> Thanks for the advice.
> Peter
>

I frequently recommend storing airplanes in these warm humid climates in
"Planeports" rather than hangars. You have to keep the sun off to prevent
damage from the UV radiation. Letting the air blow freely through seems to
prevent the dew inside phenomena. In closed hangars I have seen it actually
raining inside the hangar when it was a clear night outside!

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )

[[email protected]]

>
> Water's vapor pressure rises with temperature, if you remember your
> physics. Raising the vapor pressure drives it of sooner. It doesn't
> have to boil. 180 is a recommendation. Below that, the water might form
> in the case faster than it will evaporate, and you'll have increasing
> amounts accumulating in the engine.
>
> The research is there. Here are some who have experience in the
> area:
> http://www.sacskyranch.com/corrosion.htm
>
> http://doc.tms.org/ezMerchant/prodtms.nsf/ProductLookupItemID/JOM-0505-54/$FILE/JOM-0505-54F.pdf?OpenElement
>
> http://www.ramaircraft.com/Maintenance-Tips/Oil-Recommendations.htm
>
> http://www.memagazine.org/backissues/may99/features/vitalsigns/vitalsigns.html
>
> Lots more if you Google it.
>
> Dan

I hope you're just baiting me on this one, but you've left the door too
wide open, and I have to go through it just once. I read all four of
the web sites that you posted, and frankly I don't really see where you
might think that any of them deal with the issue that I thought we were
talking about by giving specific data on a comparison basis. You know,
like stating the moisture content and acidity of sample A is such and
such and from sample B it is such and such. So I'll comment on them one
by one.

Sacramento sky ranch...... This page shows pictures of rusted (not
dissolved or corroded by acid) lifter faces and such and talks about
how important it is to guard against it and how quickly it can occur.
It gives the same advice that we have been talking about, the
importance of frequent flights, oil changes, etc. I don't see where it
gives a comparison of oil moisture content or acidity for oil sampled
from frequently flown aircraft versus that sampled from engines that
were only ground run. Do you? If so please tell me where. We all
understand that oil eventually drains off engine parts and the moisture
in the air will cause it to rust. I thought we were discussing whether
or not oil deposited from a ground run-up would protect the cam or
corrode it, right? Like I said, many places say that you must fly often
to evaporate the moisture, but samples from each with numbers showing
how much the moisture and acidity increases to detrimental levels when
you only ground run the engine have been hard to find.

Website #2.... This is an article where a comparison of the corrosion
resistance of two different magnesium alloys is presented. I think it
best to quote a part of the article here.
From the article:
"The internal corrosion response
concentrates solely on the behavior of the alloy within the coolant
circiut of the engine."

That's means they're looking at how a new alloy's corrosion
performance compares to an old one when exposed to anti-freeze. They
didn't even consider the oil circulating through the block. Probably
because they know it doesn't corrode things but protects them. I don't
see how they answered any of our questions. The cases on my Lyc are
made from A356 aluminum, and the cam and lifters from steel and iron.
The corrosion response of a magnesium alloy to anti-freeze relates to
the corrosive effect of oil from a ground run on a camshaft just how
Dan?

website #3....RAM Aircraft....This is just mostly the same stuff as
what was on the Sac sky ranch site. Mostly good advice, but certainly
nothing that demonstrates with scientific data that oil from a ground
run has such and such moisture content and PH level. They did however
demonstrate that knowledgeable people can have different opinions. From
the article,
[RAM service history records indicate that Mineral
Based AD oils perform significantly better than synthetic and
semi-synthetic oils.]

I see that you have had better results from Aeroshell Semi-Synthetic,
;).

website #4....This article talks about new devices being developed that
are beginning to monitor in real time the chemical condition of the oil
in an engine. Didn't see data giving a comparison of the moisture
content or PH of frequently run oil versus that from a ground run here
either. Like I've said, maybe some people have done it, but I haven't
seen it published. These devices will sure make that possible though.
Maybe we will see something in the future! Yea!

I really don't think that anyone would think that those sites gave good
scientific data that supported the opinion that ground runs will
corrode your engine, but every year there are several forced landings
with fatalities, due to engine failure that would not have happened had
the engines not been allowed to rust. Maybe those engines would have
been saved had someone not been told to just let them sit if you can't
fly them. That is why I felt I should respond. After all, the ONLY
scientific data I have seen on the subject is my own oil analysis
results that told me there is 0.0% moisture in my oil sample.

I ground run maybe 6 or so times during the winter, in between flights
that is, and only when flying is not safe.

Blue skies,
Rusty

[[email protected]]

What sort of oil analysis service are you using? This outfit
here

http://www.oillab.com/oil.html

says that water is detected at levels of 1% or more using
the physical test, and most other contaminants using spectroscopic
analysis. My understanding of the spectroscopic test is that they burn
a small amount of the oil, run the light generated through a prism to
split it into its colors, and analyze the spectrum to get an idea of
the elements present. Water doesn't burn.
If they're not using the ASTM tests, your water content
numbers may be useless. 1% is a lot of water, and besides, much of the
water that may have been in your oil may have already turned to acids.
1% water in 6 quarts of oil is 2 ounces, a third of a coffee cup.
This argument could go on for a long time. It will someday
be settled when you finally get an overhaul and the technician reports
on what he finds. My experience, and the experience of many others, is
that condensation is real and it wrecks engines.

Dan

[who cares?]

In article >, "Highflyer" > wrote:

>The water in the oil will obviously evaporate at lower temperatures.
>However, when you run the engine it puts combustion byproducts into the
>crankcase. ( There is always a bit gets by those rather sloppy piston
>rings. ) These byproducts are the oxidized or "burned" results of burning a
>hydrocarbon fuel. Burnt hydrogen is H2O or water. Burnt carbon is CO or
>CO2. These wind up in your oil as a result of running the engine. The
>trick is to get the oil warm enough so that they evaporate away FASTER than
>you add them into the mixture. Then you will get the water out of the oil
>and avoid the formation of the organic acids that will cause corrosion
>inside the engine. Minor surface corrosion that is irrelevant on the
>outside of the engine may be much more serious on the inside. Yes, I have
>overhauled more engines because of corrosion than because of wear.
>
>Running the engine for a few minutes on the ground will add to the water and
>other corrosives in the oil. Then you turn it off and let it work on the
>guts of your engine. Do that if you want. I do overhauls quite
>reasonably.
>
>Running the engine for a longer time until the oil is warm enough to
>evaporate off the water on the ground? That is not so good either. By the
>time the oil is warm from ground running with most aircraft engines the
>cylinder head temps are going off scale and you are beginning to cause other
>problems from overheating. Look at all the guys shutting down from
>overheating while waiting in line for takeoff at Oshkosh after the airshow!
>:-)
>
>If you go ahead and go flying, at least a little bit, you both warn and
>distribute the oil and cool the engine. Why not go flying anyway. Isn't
>that what you have the airplane for? :-)
>


If the goal is engine preservation without flying, what would you think of
using a pre-oiler (electric oil pump) to pressurize the oil system and then
pull the prop through several blades every couple of weeks?

Would that keep all the internal parts from corroding, or will some parts
remain dry if the engine does not turn at normal operating speeds?

[[email protected]]

who cares? wrote:
>
> If the goal is engine preservation without flying, what would you think of
> using a pre-oiler (electric oil pump) to pressurize the oil system and then
> pull the prop through several blades every couple of weeks?
>
> Would that keep all the internal parts from corroding, or will some parts
> remain dry if the engine does not turn at normal operating speeds?

The cylinders won't get any oil. They rely on oil thrown off
the crank journals at idle speeds or better; some have a small hole in
the con rod to squirt oil across to the opposite cylinder, but that
hole has to be lined up with an oil gallery hole in the crank. When the
engine's running, it's a tiny squirt when the holes pass each other ,
and when the engine's off, the holes most likely aren't aligned and
won't do any good.
The inside of the case is coated with oil when the engine's
running. The cams get oil thrown at them while it's running. The gears
rely on rotation and drip for lube. Cranking the engine or pulling it
through by hand doesn't do a really good job of moving the oil around.

Dan

[Stuart & Kathryn Fields]

Hell I live in the Mojave desert. It isn't real dry here but you can win a
prize and a free medical exam if you can spit on the sidewalk here.

--
Kathy Fields
Experimental Helo magazine
P. O. Box 1585
Inyokern, CA 93527
(760) 377-4478
(760) 408-9747 general and layout cell
(760) 608-1299 technical and advertising cell

www.vkss.com
www.experimentalhelo.com


> wrote in message
oups.com...
> I just watched a program about the huge Oresund bridge between Denmark
> and Sweden, and there was a segment about how the corrosion problem for
>
> the bridge was dealt with. Instead of painting, they use sealed
> compartments that have the air humidity kept below 60%. This they said
> eliminates corrosion. This started me thinking about the corrosion we
> aircraft owners are told to guard against, since I have personally been
>
> told by an overhaul shop, that half of all the engines he sees that
> need work, need it because of corrosion. There are several "facts" that
>
> I am beginning to question as to their validity. The ones that come to
> mind are:
>
> 1) You have to get the oil up to 180 deg F or the water in the oil
> won't evaporate.
>
>
> 2) Starting and ground running the engine for a minute or so is the
> "worst" thing you can possibly do.
>
>
> 3) Flying for an hour will "clean" the oil (or at least evaporate the
> water, preventing acid formation) so that it doesn't turn to acid and
> dissolve the engine while sitting idle.
>
>
> There are probably some others, but these three stand out the most
>
> to me. Now I am sure that what I am about to say will not go over well
> with some people, but I have the asbestos suit ready and waiting.
> My take is that these three "facts" are a bunch of poppycock. Why
>
> or how they got started is anyone's guess, but the reasoning behind
> some of them is understandable, for others I wonder what they were
> smoking at the time. My thoughts are along these lines, and I admit I
> could be wrong, but I don't think so.
>
>
> Concerning fact #1...Why does someone think that the water has to be
> brought to a boil before it will evaporate. Water evaporates very well
> even at sub-freezing temperatures,much less at the warm to hot temps
> created in a running engine. And at say 140 F, I can't help but believe
>
> that any water or moisture in the engine will be purged quickly. With
> water at that temp you can literally see clouds of vapor escaping, and
> this is well below boiling. Not that the hotter the engine gets the
> water doesn't evaporate more quickly, it does I'm sure. It's just that
> in the engine cases which are open to the air at the breather tube and
> elsewhere, any heat above say 85 F or so will be more that enough to
> dry out the oil in the crankcase. As evidence of this, I ground run my
> engine all the time and have for many years. I live in a VERY humid
> climate. The oil analysis reports I have done on a regular basis by
> Blackstone have never shown any trace of water or moisture. I recently
> tore done the engine for rebuild after more then 15 years of perfect
> service, and the cam lobes, lifter faces, and every part in the engine
> was shiny and totally free from rust or any other corrosion.
>
>
> Concerning fact #2.... We all constantly clean and oil many of the
> things we own such as tools, etc. It is the layer of oil that prevents
> the rust. I accept that if the oil is too acidic it could corrode or
> "chem mill" the metal, but it takes highly acidic liquid to do that,
> and the oils I use have acid buffers in them to deal with mild acidity.
>
>
>
> Running is the only way to re-oil all the parts in the engine,
> especially the cam and lifters. Just like oiling the machinists tools
> that I own keeps them rust free, oiling the engine keeps it rust free I
>
> would think.
>
>
> Concerning fact #3.... This is the one that really makes me wonder. If
> oil needs to be changed every 25-50 hours, how does flying for an hour
> clean it? I can't help but think that the longer the oil is used the
> dirtier it gets. I guess they think that it's "really" dirty just after
>
> starting, and you "clean" it as you fly.
>
>
> In closing, it seems to me that many of the things we are told are
> contradictory on this subject. I have witnessed many OWT come and go in
>
> my time, so common knowledge isn't always correct. Lean of peak
> operation comes to mind. Some blockheads still don't think George Braly
>
> has it right.
>
>
> Blue Skies
> Rusty
>

[[email protected]]

As I posted previously, I use Blackstone labs for my oil analysis,
which is a popular lab for GA pilots. They have stated many times that
there was no water or fuel found in my oil sample. I seriously doubt
that a trace amount of water in the oil would cause it to corrode metal
anyway, since it is still mostly oil which protects it.

Rusty


wrote:
> What sort of oil analysis service are you using? This outfit
> here
>
> http://www.oillab.com/oil.html
>
> says that water is detected at levels of 1% or more using
> the physical test, and most other contaminants using spectroscopic
> analysis. My understanding of the spectroscopic test is that they burn
> a small amount of the oil, run the light generated through a prism to
> split it into its colors, and analyze the spectrum to get an idea of
> the elements present. Water doesn't burn.
> If they're not using the ASTM tests, your water content
> numbers may be useless. 1% is a lot of water, and besides, much of the
> water that may have been in your oil may have already turned to acids.
> 1% water in 6 quarts of oil is 2 ounces, a third of a coffee cup.
> This argument could go on for a long time. It will someday
> be settled when you finally get an overhaul and the technician reports
> on what he finds. My experience, and the experience of many others, is
> that condensation is real and it wrecks engines.
>
> Dan

[Roger]

On Mon, 24 Apr 2006 19:25:08 +0800, Stealth Pilot
> wrote:

>On Sun, 23 Apr 2006 22:45:06 -0400, "J.Kahn"
> wrote:
>
>
>>>
>>You don't really need to fly it once a week. Once a month will do as
>>long as it gets an hour or so.
>
>an hour or two *after* the engine temperature is at the normal running
>temp range will see it right.
>
>white oil? fill it up with avgas and fly out the tank in one
>uninterrupted flight and it should be black again.

An hours flight will remove the water and I already use 100LL.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

>
>my aircraft occasionally sits for longer than I want and I find on a
>long cross country that by the end of the second day's flying it is
>running like a well oiled sewing machine again. flying for shorter
>periods never seems to get the sewing machine effect where it runs
>noticeably sweeter.
>
>Stealth Pilot

[Roger]

On Sun, 23 Apr 2006 18:43:26 -0400, Roger
> wrote:

>On 23 Apr 2006 02:18:53 -0700, wrote:
>
>>Ernest,
>>
>> I agree with alot of what you said. The point of my OP was not to
>>challenge what the best care of the engine is. I think we all agree
>>that flying it an hour a week is what is called for, along with regular
>>oil changes. What I has me concerned is that many times during the
>>winter, it is difficult if not impossible to do this. In that
>
>Get a good engine block and cylinder head heater. Wrap up the entire
>cowl with plenty of good thermal blankets and use an engine heater to
>keep the oil dry.
>
I should add that keeping the heater on all the time comes with some
caveats. One being the whole engine has to get hot and in most
climates where it's necessary to preheat the engine that means
thoroughly wrapping up the front of the airplane from the firewall
forward. The blankets I've cut go half way up the windshield and
behind the cowl flaps.

Some one asked about this and I can't find the post.

I regularly check the engine by pulling the dip stick. If things
aren't hot enough there will be moisture condensing under the top of
the dipstick or oil filler cap.

Everything on the engine gets hot enough that it's uncomfortable to
put your hand on it. You can do so without getting burned, but if you
are not expecting it, you will jerk your hand back away from the
cylinders. Based on that I'd guess the temp is pretty close to 50C or
about 122F (if I did the math right) That's not 180, but it's not
getting combustion products put in at the same time either.

Another caveat is; don't leave the thing set for more than a couple of
weeks. The engine is hot enough the "cling" will quit clinging.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
>>situation, I think it is better to warm up the engine than just let it
>>sit. The cam and lifter on Lycomings will tolerate no rust at all. Once
>>you have even a small rust pit in the lifting face of the cam or lifter
>>I'm afraid you are looking at a tear down in the not too distant
>>future. Literally beats them to death in short order. And like I said,
>>my oil analysis results show no water at all, zero. As for the engine
>>making water, of course it does, and it goes right out the exhaust as
>>you said. I don't think the engine stays very cold for any length of
>>time once running. Those babies get hot, and quick, even in the winter.
>>I doubt if they collect much if any water during start up. I also don't
>>think the oil turns to an acid capable of dissolving the engine. I
>
>Again we disagree. If I don't use the engine heater the oil will be
>almost milky within the first five hours. Using the heater it's still
>clear to around the 20 hour mark. OTOH my engine has no oil filter so
>the oil changes come at 25 hours. In 25 hours the oil doesn't go down
>enough to hardly see on the dip stick, so it's using less than a pint
>in 25 hours and is almost at TBO. BTW it has a wet vacuum pump.
>
>Roger Halstead (K8RI & ARRL life member)
>(N833R, S# CD-2 Worlds oldest Debonair)
>www.rogerhalstead.com
>
>>could be wrong, as I haven't done the research, but then, I don't think
>>anyone else has either. Some say they have, but they aren't showing it
>>for us to see, at least not that I'm aware of. I realize that the 180
>>deg is probably meant as a guide, but they do state specifically that
>>if you don't hit 180, the water won't evaporate. I think this is
>>nonsense. The oil in a running engine is literally blown and slung
>>around like a hurricane. It doesn't just sit at the bottom of the sump.
>>And the volume of oil pumped is huge. 90 psi will do that. I think that
>>there probably are pockets within the engine that trap water. The front
>>of the hollow crank comes to mind, but I don't think they ever get
>>purged of their water, even after hours of operation.
>>
>>Blue skies,
>>Rusty

[Ernest Christley]

who cares? wrote:

>
> If the goal is engine preservation without flying, what would you think of
> using a pre-oiler (electric oil pump) to pressurize the oil system and then
> pull the prop through several blades every couple of weeks?
>
> Would that keep all the internal parts from corroding, or will some parts
> remain dry if the engine does not turn at normal operating speeds?
>

Any container with a small opening will act as a water pump over time.
During the day, the container will warm up and push out the air inside
it. As the temps drop in the evening, the container will cool and pull
in air. Since it is evening, that air will be laden with dew. The dew
will collect in the bottom of the container.

In the morning the process repeats, except the air is pressed out the
top...leaving the droplet of dew in the bottom. If something doesn't
occur to get rid of that droplet of dew, another droplet will be added
the next night..and the next...and the next.

Adding to what Dan said, when the fuel does burn, it will push H20 and
CO2 past the rings. That's a neat mixture. It was used as an
antiseptic around the turn of the last century. It's called carbonic
acid, I believe.

--
This is by far the hardest lesson about freedom. It goes against
instinct, and morality, to just sit back and watch people make
mistakes. We want to help them, which means control them and their
decisions, but in doing so we actually hurt them (and ourselves)."

[[email protected]]

>I should add that keeping the heater on all the time comes with some
>caveats. One being the whole engine has to get hot and in most
>climates where it's necessary to preheat the engine that means
>thoroughly wrapping up the front of the airplane from the firewall
>forward. The blankets I've cut go half way up the windshield and
>behind the cowl flaps.

The problem with keeping an engine too warm all the time:
degraded rubber hoses, seals and gaskets. Rubber parts lose their
lighter elements faster when hot and get hard; they shrink, crack and
leak. They'll do it over time too, of course, but heat accelerates it.
The same thing applies to aircraft interiors and radios when subjected
to the heat of the sun.
Nothing lasts forever. We don't want to think about that
sometimes. Your airplane is aging whether it's flying or not, and you
can only slow it as much as practicable. I would be more inclined to
use dessicant plugs (with "Remove Before Flight" flags attached) on the
engine breather, exhaust and intake. Cheaper than heating and easier on
rubber.

Dan

[Roger]

On 28 Apr 2006 07:52:31 -0700, wrote:

>>I should add that keeping the heater on all the time comes with some
>>caveats. One being the whole engine has to get hot and in most
>>climates where it's necessary to preheat the engine that means
>>thoroughly wrapping up the front of the airplane from the firewall
>>forward. The blankets I've cut go half way up the windshield and
>>behind the cowl flaps.
>
> The problem with keeping an engine too warm all the time:

The Key here is the word "too". The Tanis heater doesn't keep the
engine too hot.

>degraded rubber hoses, seals and gaskets. Rubber parts lose their
>lighter elements faster when hot and get hard; they shrink, crack and
>leak. They'll do it over time too, of course, but heat accelerates it.
>The same thing applies to aircraft interiors and radios when subjected
>to the heat of the sun.

The entire plane including the interior gets a lot hotter out in the
sun than the engine does from the heater.

> Nothing lasts forever. We don't want to think about that
>sometimes. Your airplane is aging whether it's flying or not, and you
>can only slow it as much as practicable. I would be more inclined to
>use dessicant plugs (with "Remove Before Flight" flags attached) on the
>engine breather, exhaust and intake. Cheaper than heating and easier on
>rubber.

On many you can not get to the intake to put in a desiccant plug in a
manner that would do any good. Just stuff a tennis ball in the
exhaust(S). If you forget them it's no problem as they will be gone
before the first cylinder fires. OTOH if they stick for some reason
they'll be gone right after the first cylinder fires, but they may be
more difficult to find.

The place where desiccant plugs do the best is when they are put in
place of spark plugs. OTOH they have to be replaced every two weeks
or so. If the engine is going to set that long, I'd think it'd be
better to make sure the oil is clean, pull the plugs and spray oil
into the cylinders and then insert the plugs or desiccant plugs.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com



>
> Dan