Cold Starts

On Mon, 16 Feb 2004 04:08:04 GMT, "Travis Marlatte"
wrote:

So, for those of you with plug in heaters, how does that work out? I presume
that at your home airport, you are parked in your own unheated hangar or
near an outlet on the ramp. What about visiting other airports? Do you asked
to be parked near an outlet? Do they stretch a cord across the ramp for you?
Do they plug it into a service truck for a couple of hours before start?

-------------------------------
Travis


If I cannot plug in, I obtain pre-heat in the usual manner -- i.e. the FBO
either has a gas fired unit; heated hangar or I make other arrangements.

Some folk will carry small generators; others will carry small "Red
Dragons".


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Those little Honda 1000's at 29# would be the cats pajamas.

If you could keep it from growing legs....

Mike Z

"Viperdoc" wrote in message ...
Is it worth lugging long extension cords to plug in the Tanis heaters for my
Baron if it's going to sit outside at 12 degrees for two to three hours
after a flight?

I have cowl plugs which may help a little, but is it really a problem? The
oil will be well circulated, and the battery is in good shape to crank the
engines.

Also, the POH says to keep the cowl flaps open during taxi and take off, but
when it's so cold outside does this still make sense? As long as the CHTs
remain within a reasonable range what difference should it make?

Thanks from Wisconsin, where its 2 degrees and clear.

I started my engines this morning at -4 F... No preheat never do

Wow. Pretty cavalier attitude with two engines worth close to $20K apiece.

I've found that for periods of four hours or less, the engine will stay
pretty warm with our dark blue cowl cover on -- especially in a bright sun.

For longer periods, plugging in is essential. A couple of weeks ago, while
staying at Lake Lawn Lodge (in Lake Delevan, WI) the oil temperature was 34
degrees at start-up -- even after being plugged in overnight, WITH the cowl
cover on!

The outside temperature was -10, and the wind was howling.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Well, there's preheats and there's preheats...
A quick preheat with a red dragon makes you feel warm all over (so does
urinary incontinence while wearing a dark wool suit) but doesn't do much of
anything except make the exterior sheet metal, fins, etc., temporarily
warm... The oil is still at ambient in the pan, and definitely ambient upon
entering the oil pump... And that great steel slab of rotating oil passages
they call a crank is still at -4 degrees, or whatever, to the oil trying to
flow through it - chilling the 'supposedly' warm oil quite nicely and
instantly...
notice that the crank has two or more 'ambient temperature equalizing heat
sinks' firmly attached......
Of course, you feel all warm and secure - if not actually doing a lot for
the engine - so I suppose that's worth something...

Same deal for an oil pan heater... You have a puddle of relatively warm oil
(often with a chilled center if it is the typical preheat) that will assume
crank/prop and case temperatures immediately upon flowing into the
passages...

If you read the aggregate wisdom of the alaskan/arctic flyers, you will see
that a preheat includes a solid hour - and usually more - of a red dragon
with the pedal to the metal, cowl blankets and prop booties, pouring the
heated oil (from a stove) into the engine and immediately starting...

Now the Reif, et. al., systems of cylinder clamps and pan pads can be
helpful IF they are on for a number of hours with an good, metallized,
insulated, blanket tightly wrapped, booties on the prop and hub, and no air
blowing up the exhaust, to allow the heat to soak all the way to the center
of the crank... Less effort than that and you are kidding yourself...


denny

"Dale" wrote in message "Dennis O'Connor"
wrote:

I started my engines this morning at -4 F... No preheat never do
That's the way this airplane has been treated ever since
semisynthetic, multiviscosity, oils came out.... Engines go to TBO
routinely...

Wow. To each his own. I would never start at those temps without
preheat, and I also used 15W50. I've also tried to pour it when it's
cold. G If it works for you, great.

"Dennis O'Connor" wrote in message
...
Well, there's preheats and there's preheats...
A quick preheat with a red dragon makes you feel warm all over (so does
urinary incontinence while wearing a dark wool suit) but doesn't do much
of
anything except make the exterior sheet metal, fins, etc., temporarily
warm... The oil is still at ambient in the pan, and definitely ambient
upon
entering the oil pump... And that great steel slab of rotating oil
passages
they call a crank is still at -4 degrees, or whatever, to the oil trying
to
flow through it - chilling the 'supposedly' warm oil quite nicely and
instantly...
notice that the crank has two or more 'ambient temperature equalizing
heat
sinks' firmly attached......
Of course, you feel all warm and secure - if not actually doing a lot for
the engine - so I suppose that's worth something...

Same deal for an oil pan heater... You have a puddle of relatively warm
oil
(often with a chilled center if it is the typical preheat) that will
assume
crank/prop and case temperatures immediately upon flowing into the
passages...

If you read the aggregate wisdom of the alaskan/arctic flyers, you will
see
that a preheat includes a solid hour - and usually more - of a red dragon
with the pedal to the metal, cowl blankets and prop booties, pouring the
heated oil (from a stove) into the engine and immediately starting...

Now the Reif, et. al., systems of cylinder clamps and pan pads can be
helpful IF they are on for a number of hours with an good, metallized,
insulated, blanket tightly wrapped, booties on the prop and hub, and no
air
blowing up the exhaust, to allow the heat to soak all the way to the
center
of the crank... Less effort than that and you are kidding yourself...


denny

How come the engine in my car with 190,000 miles is running fine with no
signs of undue wear with nary a single preheat. It is often started at
temps well below 0 F. Aluminium block, steel crank, steel cylinder liners
and aluminium pistons same as the ole Continental.



"Dale" wrote in message "Dennis O'Connor"
wrote:

I started my engines this morning at -4 F... No preheat never do
That's the way this airplane has been treated ever since
semisynthetic, multiviscosity, oils came out.... Engines go to TBO
routinely...

Wow. To each his own. I would never start at those temps without
preheat, and I also used 15W50. I've also tried to pour it when it's
cold. G If it works for you, great.

Dave Stadt wrote:

How come the engine in my car with 190,000 miles is running fine with no
signs of undue wear with nary a single preheat.

Aircraft engines are usually designed to turn at about 2700 rpm max. Auto
engines are designed to turn about 5000 to 6000 rpm max. Since the valves are
closing much more rapidly on an auto engine, the springs must be made much
stiffer. Since these stiffer springs slam the valve head against its seat with
much more force, the valves are made much thicker to take the punsihment.

In short, the entire valve train of an aircraft engine is much more delicately
built than that of an auto engine. Skip the preheat, and you run a serious risk
of snapping a valve.

George Patterson
A diplomat is a person who can tell you to go to hell in such a way that
you look forward to the trip.

In article , "Dennis O'Connor"
wrote:

Well, there's preheats and there's preheats...
A quick preheat with a red dragon makes you feel warm all over (so does
urinary incontinence while wearing a dark wool suit) but doesn't do much
of
anything except make the exterior sheet metal, fins, etc., temporarily
warm... The oil is still at ambient in the pan, and definitely ambient
upon
entering the oil pump... And that great steel slab of rotating oil
passages
they call a crank is still at -4 degrees, or whatever, to the oil trying
to
flow through it - chilling the 'supposedly' warm oil quite nicely and
instantly...
notice that the crank has two or more 'ambient temperature equalizing
heat
sinks' firmly attached......
Of course, you feel all warm and secure - if not actually doing a lot for
the engine - so I suppose that's worth something...

well, I've done the no-preheat thing on a 30 degree day and the prop
didn't spin all that fast (barely started). With a preheat on a
20 degree day the prop spins a lot faster. Preheating does something
for my engine.

--
Bob Noel

Well,,,desperate men do desperate things.

Stay at a motel near the airport and go out and start your plane and
run it for 1/2 hour every 4 hours. Bring the walkman.

Dave Stadt wrote:
: How come the engine in my car with 190,000 miles is running fine with no
: signs of undue wear with nary a single preheat. It is often started at
: temps well below 0 F. Aluminium block, steel crank, steel cylinder liners
: and aluminium pistons same as the ole Continental.

Two words: Liquid cooling. Everything about the aircraft engine is catered to
running at ridiculously high temperatures during normal operation. The oil is very thick
so it still lubricates at high temperatures and carries heat away from the cylinders. The
cylinders themselves have choke (they're slightly smaller bore at the top), with the
thought being they'll expand to be straight when they heat up during normal operation.
Those two things are the primary reasons.... lack of oil and scuffing of cylinders.

-Cory

--
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* The prime directive of Linux: *
* - learn what you don't know, *
* - teach what you do. *
* (Just my 20 USm$) *
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wrote in message
...
The oil is very thick

Is there any difference in viscocity between a 15/50 aero oil
and a 15/50 car oil?

Paul