Engine Corrosion

[vanNostrum]

[Colonel]

One word: Camguard

They hint that corrosion varies. Of course it does. Just like cars are destroyed
by the salt in Canada, aircraft engines (and airframes) are quickly destroyed by
hot, humid, saline environments. In these hostile conditions, even daily operation
of an engine may not be enough to stop internal corrosion.

Decades ago, I remember Freddy had a Pitts S-2A that he flew every day in Key West,
and the camshaft still went on it.

Conversely, if you are in a cold, dry, salt-free environment your engine may last a
very long time, even without frequent operation.

It's really simple. Camguard and a Battery Tender Jr for any private aircraft unless
you're ok with this:

[Scudrunner]

This thread should be required viewing / reading.

It always bugs me to see planes sit.
And it irks me perhaps more than it should when I read ET of 500 hours SMOH in 1990. And they’re asking a premium for price for it.

Up north every plane we flew went well beyond TBO because they where flown properly and consistently.

Honestly would rather have 3 or 4 other pilots involved in ownership of a plane and have it fly 200-300 hour a year vs the average of 50 most Private flyers log. Plane would be better off.

[John Swallow]

Andrew:


How much do you use? As per the article? More? Less?

https://www.aviationconsumer.com/mainte ... uire-time/

[digits]

And it irks me perhaps more than it should when I read ET of 500 hours SMOH in 1990. And they’re asking a premium for price for it.

Ugh. Yes. And then even when willing to pay said premium, they don't want to allow a cylinder pull to prove the condition. Just silly.

"it's less than a quarter time engine!"
- "actually it's 18 years past a 12 year TBO"

[Colonel]

With modern camera technology, you don't need to pull a cylinder any more
to verify the condition of

1) the cylinder walls
2) the valves
3) the camshaft lobes



Ask Mike Busch about the dangers of pulling cylinders in the field. He's seen
it fucked up so many time, he thinks it should only be done in an engine shop.

Mike has a point. The Lycoming DD overhaul manual is missing some really
important info. I'm sure if you took at course at Williamsport, they would give
you a thick binder of SG/SL/SI which fill in the gaps, but ...

Camguard can be run in two concentrations - roughly, 5% as a corrosion
inhibitor and 10% as a preservative oil (see the docs for exact figures, which
of course change every time you add a quart).

Personally, I don't care what it costs. If you use it, the inside of your engine
will be like new. I like enough of it, that I can smell it on final, with the power
off.

Camguard has the weird side effect of getting rid of valve sticking when an
aircraft sits. I have had terrible trouble with this, and Camguard magically gets
rid of it. I have no idea how an anti-corrosion additive at the same time removes
deposits. Fucking magical. I should have paid more attention in undergrad
Chemistry but I was too busy getting laid. Or let's be honest, trying to.

[Colonel]

it's 18 years past a 12 year TBO

Core value only at that point.

[digits]

With modern camera technology, you don't need to pull a cylinder any more
to verify the condition of

1) the cylinder walls
2) the valves
3) the camshaft lobes

Any idea if this can be done on a Lycoming IO-320-B1A? If so, how?

Haven't found a mechanic yet who is able to tell me the condition of the camshaft without pulling a cylinder.

[Colonel]

Any idea if this can be done on a Lycoming IO-320-B1A?

Of course. Vividia VA-400. Kudos to Photofly. He doesn't have a PhD
like Jill Biden (actually, he might - I never asked what his four degrees
were) but he's pretty good with a camera. Photo. Fly. Get it? He told
me to order it, and I always do what he tells me to. He signs my insurance
off that I am capable to land a taildragger. I am not making this up.

Haven't found a mechanic yet who is able to tell me the condition of the camshaft without pulling a cylinder.

Here's something else your mechanic doesn't know: even if you pull one
cylinder and those cam lobes look good, others might be trashed. Some
do double duty. You need to look at ALL of them.

[Colonel]

Ok. You own a private aircraft and you don't fly as much as you'd like to.
You probably don't even fly 50 hours a year. The average is much less.
You might only fly 10 hours a year!

How I do maintenance for infrequently-flown aircraft:

In the springtime, drain the oil. If you have a pressure screen, remove it
and rinse the contents out onto a white cloth with mineral spirits to get
rid of oil and carbon deposits. Take a picture and mail it to yourself, so
you can watch the trend over the years. If it looks like this, you're fucked:



Lycoming actually talks about how much metal is acceptable. I am not
making this up.

If you have an oil filter, pull it and cut it open with a can opener and do
the same thing as with the pressure screen. Unfold the filter, rinse it
out and look for metal. Take a picture of how much you got.

Oil analysis is a complete waste of time, IMHO. Spend a few minutes
and look at how much metal your engine is making, as described above.
Most people don't bother, which is weird.

It's springtime, so buy a cheap straight grade oil. W80 or W100, whatever
you want. Halve the number to get the SAE viscosity, btw. If you have a
four cylinder, add a pint of Camguard to 5 quarts oil, which is 1/11 pints
or 9%, which I like. Smell it on final. Mmmmmm.

If you're running a six cylinder with a slobber pot like me, I like to run the
mother full at 12 quarts, all the time, because I have a wet sump, which
is a really weird design decision. I add 11 quarts and two pints Camguard,
which is 2/23 or 8.7% .....MMMmmmm.


When winter comes on, oil change again. Same pressure screen or oil
filter dance. I hate oil filters, btw. Every time I buy an aircraft with one,
I get rid of it. Does not pass basic cost/benefit analysis.

Buy a cheap multigrade oil, like Philips X/C 20W50. You know. Cat piss,
but it's ashless dispersant. Add Camguard as above.

I am not a fan of Aeroshell 15W50 or the "plus" W100+ oils with the same
package. It is expensive, makes your engine leak, and does not inhibit
corrosion as well as Camguard. You are better off buying a cheap oil,
and making it a very expensive oil with Camguard, which is what it was
developed for, but the suits shut it down.

TL;dr

For private aircraft, I do two oil changes a year. Straight grade in the summer,
multi-grade in the winter, as much Camguard as your wallet can stand. Spruce
sells it in four-pint packages.