Oil change questions

I never fully trust the snap type torque wrenches & would put more
faith in the bending beam type (which one do you call cheap &
uncalibrated?). Unless the snap type is calibrated before use, there
could be quite a bit of error in it. The beam type only has to return
to zero after each use.

Anyone else have similar or different thoughts on this? The world
seems to have gone to snap types.

On 8 Jul 2005 12:36:56 -0700, "nrp" wrote:

I never fully trust the snap type torque wrenches & would put more
faith in the bending beam type (which one do you call cheap &
uncalibrated?). Unless the snap type is calibrated before use, there
could be quite a bit of error in it. The beam type only has to return
to zero after each use.

Anyone else have similar or different thoughts on this? The world
seems to have gone to snap types.

I've got a guaranteed 4% accurate $napOn clicker that comes through
cal within the 4%, but needs tweaked about every other year.

Don't do much of it anymore, but have got a Mac Tool$ bender ($10 at a
garage sale) that gets cal'ed every year (heh) that gets used for
cylinder bases & other mission critical stuff.

Like you said, if a bender reads O, it's extremely likely to be OK.
Cheap clickers tend to crunch instead of click, but have one in the
shop that gets sent every 12 months and gets tweaked about every three
years (that would be LESS often than my $napOn)

Toughest thing to do with a properly cal'ed clicker is not pull it
through the click & over-torque a little.

TC

Jimmy B. wrote:

What do you all do? Torque to the specification, or just 1 turn?

Torque to specs. I also use the Dow lubricant on the gasket instead of engine oil.

What is your opinion?

Lycoming says to change the oil in the O-320 series every 4 months or 50 hours
of operation, whichever comes first. IIRC, Continental said 4 months or 25 hours
with the O-200 with a screen. The recommendation for a 3 or 4 month change
period is pretty widespread. I'd be looking for another mechanic.

George Patterson
Why do men's hearts beat faster, knees get weak, throats become dry,
and they think irrationally when a woman wears leather clothing?
Because she smells like a new truck.

George Patterson wrote:
Jimmy B. wrote:


What do you all do? Torque to the specification, or just 1 turn?


Torque to specs. I also use the Dow lubricant on the gasket instead of
engine oil.

What is your opinion?


Lycoming says to change the oil in the O-320 series every 4 months or 50
hours of operation, whichever comes first. IIRC, Continental said 4
months or 25 hours with the O-200 with a screen. The recommendation for
a 3 or 4 month change period is pretty widespread. I'd be looking for
another mechanic.

The more I deal with this mechanic, the less I like him. For example, I
have a Precise Flight standby vacuum system, and the indicator light is
out. When I told him about it, his response was that not everything has
to work. I told him that without the light, I would not know that my
vacuum pump has failed until I got high enough in altitude that the
Precise Flight system could not produce enough vacuum and by then, I
could be in or above IMC. He just shrugged and walked away.

For planned maintenance, it is easy to go to another shop, but he's the
only mechanic on the field and I do want to stay on good terms with him
just in case I need something done and the plane is unflyable.

I would like to find a free-lance mechanic that could come to my field
to do work.



George Patterson
Why do men's hearts beat faster, knees get weak, throats become dry,
and they think irrationally when a woman wears leather clothing?
Because she smells like a new truck.

Tell him to fix it. If he won't find another mechanic who will. Don't
tell him you are taking it to another mechanic. It's none of his
business. Don't **** him off, just do what you have to do to maintain
the airplane. The light should work. I think, ideally, EVERYTHING in my
plane should work. But it is UP TO YOU. Don't let a mechanic, or me,
dictate the maintenance of YOUR airplane. It is your property, you are
in charge of it.

Jimmy B. wrote:

For planned maintenance, it is easy to go to another shop, but he's the
only mechanic on the field and I do want to stay on good terms with him
just in case I need something done and the plane is unflyable.

I would like to find a free-lance mechanic that could come to my field
to do work.

Yeah, that would be nice, but it looks like you're stuck with this guy for now.
Here's what I would do in your shoes. Don't ask this guy any questions if you
can help it. When something needs to be fixed, ask him to fix it, and try to do
it in such a way that he won't feel comfortable arguing.

I once had to deal with a mechanic who had similar ideas to your man (mine would
never have recommended postponing oil changes, however). Pete's problem was that
he dealt with cheapskate pilots so much that he just assumed that everybody
would want to take shortcuts. Once I had a bad plug wire and he recommended
replacing just the bad one. When I told him to put in a new set of plug wires
instead, he did what I asked. After I explained that all the wires were the same
age and I didn't want to be bringing the plane back in every few months to
replace another one, he understood. After that, we could discuss alternatives
for each job of work. Sounds like that approach isn't working for you, though.

George Patterson
Why do men's hearts beat faster, knees get weak, throats become dry,
and they think irrationally when a woman wears leather clothing?
Because she smells like a new truck.

Another thing that is a MUST with the clicker torque tools is to unload
them after each use. Do not leave them set to a torque.

Regards, Ross
C-172F 180HP
KSWI


wrote:
On 8 Jul 2005 12:36:56 -0700, "nrp" wrote:


I never fully trust the snap type torque wrenches & would put more
faith in the bending beam type (which one do you call cheap &
uncalibrated?). Unless the snap type is calibrated before use, there
could be quite a bit of error in it. The beam type only has to return
to zero after each use.

Anyone else have similar or different thoughts on this? The world
seems to have gone to snap types.


I've got a guaranteed 4% accurate $napOn clicker that comes through
cal within the 4%, but needs tweaked about every other year.

Don't do much of it anymore, but have got a Mac Tool$ bender ($10 at a
garage sale) that gets cal'ed every year (heh) that gets used for
cylinder bases & other mission critical stuff.

Like you said, if a bender reads O, it's extremely likely to be OK.
Cheap clickers tend to crunch instead of click, but have one in the
shop that gets sent every 12 months and gets tweaked about every three
years (that would be LESS often than my $napOn)

Toughest thing to do with a properly cal'ed clicker is not pull it
through the click & over-torque a little.

TC

If you have any oil contamination factors such as using primarily 100LL
fuels, a lot of engine blowby, and are not able to control the
operation for minimum contamination, I agree the oil should be changed
fairly often. But I have a 1700 hr TTSN O-320E2D in a 172M that now
only flys about 30 hrs/year. I change oil (and always filter too) only
every year since the oil stays unusually clean. It takes nearly 20
hours before it even loses its green and gets coffee colored. At change
I've randomly checked the oil analysis and it always comes back normal.

The oil was Mobil straight grade during its initial 700 hours and has
been Shell 20W50 for the last 1000 hrs. We are based in a low
contamination area (Minnesota and Wisconsin), and burn 80 Octane or
autofuel to minimize lead contamination. When we were flying it more,
we changed oil only every 50 hours. Consumption remains 1 qt every 30
hrs. The engine remains quite cold blooded on CHT and oil temp.

I climb at higher airspeeds, cruise it leaned and with lower power
settings, avoid 100LL, am careful to purge the combustion products on
shutdown, always preheat but don't continuosly heat during the winter,
& watch the baffling and engine external cleanliness. Interestingly it
never has had particularily good compression numbers, but always has
had excellent "bounce"