Private Aircraft Engines

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Colonel
Posts: 3450
Joined: Wed Apr 29, 2015 10:31 am

If you don't fly or care about private aircraft,
please skip this thread.

But if you own or operate a private aircraft,
you might be interested to learn that the
engines in these aircraft are totally different
than engines in commercial aircraft which
are flown frequently and as such wear out
at TBO (or so the theory goes).

Private aircraft engines rarely wear out -
they rarely make flight time TBO.  At 35
hours per year and a 2000 hour TBO, that's
over 50 years (!) and we all know that private
aircraft engines don't last 50 years.

Private aircraft engines don't wear out -
they rust out internally, start making
metal and need an expensive overhaul
(tens of thousands of dollars) which often
is about the value of the aircraft!

I should mention that there are two common
piston engines in use in aircraft:

Lycoming
Continental

and they are completely different in
this respect.  I have both, and am pretty
agnostic in this regard.

A Lycoming engine is good for a commercial
operator that flies it frequently (so it doesn't
corrode internally) and the cylinders are
amazingly resistant to cracking due to really
abusive handling by pilots.

A Continental engine is better for a private
aircraft because it handles the abuse of being
parked incredibly well - it has much less internal
corrosion than a Lycoming.  However the cylinders
just aren't up to the abuse that a poorly-trained
low-time pilot will inflict on them, such as a four-bars
who might know turbines, but knows nothing about
piston engines.

The best thing you can do for a private aircraft
engine is to fly it frequently - I suggest at least
once every two weeks.  If we refer to Lyc SB180B
it recommends pickling after 30 days. 

All these lengths of time are subject to conditions
such as temperature, humidity and salinity.

When you fly it, you want to get the oil temp up
to at least 150F indicated, to try to boil the water
out of the crankcase.  This can be a problem in
the winter for some aircraft.

Here's a really good tip:

After flying your private aircraft, if it's not too
dusty, pop the oil access door open and prop
open the dipstick tube (Lyc) or take off the oil
filler cap (TCM) and allow convection to carry
the moisture out of the hot engine, like a
chimney.  Get that moisture out!

One last thing:  I really, really hate snake oil
additives (ironic for a guy with cases of AvBlend
and Camguard) but if you have a private aircraft
with a Lycoming, google Camguard and do some
reading.

The cam lobes and flat tappet lifters on your
Lyc engine are so terribly vulnerable to internal
corrosion, Lycoming has gone to roller lifters.
Your nitrided steel cylinders are equally vulnerable.

Anyways, with a little effort you can avoid a
premature engine overhaul, and postpone
spending tens of thousands of dollars.  That
might not be much money to you, but it's not
chump change to me.

I remember telling a private aircraft owner
to not let his Lycoming IO-540 engine sit,
and he told me he didn't care about the
engine rusting out and needing a very
expensive overhaul.

Sure enough, after a year, this is what the
inside of his Lycoming looked like:

[img][/img]

and sure enough, he took a $30,000 hit in the
selling price.

Here's what one of my Lyc IO-540 engines looks like:

[img][/img]

I guess I'm just not very smart, compared to
you guys that tell me how stupid I am, all
the time.


Colonel
Posts: 3450
Joined: Wed Apr 29, 2015 10:31 am

[quote]we all know that private aircraft engines don't last 50 years[/quote]

I lie like a rug.  There are always exceptions.

As I mentioned, TCM engines are amazingly
resistant to internal corrosion.  At my tiny
airport, a really strange private aircraft owner
(is there any other kind?) parked his Bonanza
for almost 20 years.  Just changed the oil and
closed the hangar door.

An AME bought it for parts, and was amazed
that the airframe and engine were actually ok -
no salt in the air here.  And I was lucky enough
(!) to do the first test flights on it.  Last I heard,
it's in BC now - the new owner flew it out there
and is having a great time with it.

You couldn't do that with a Lycoming.  It would
have been pooched after a year or two.

Back to my quote above:

[quote]we all know that private aircraft engines don't last 50 years[/quote]

Here's a TCM IO-360 engine with 1966 on the
crankcase that's never been apart:

[img][/img]

I've popped the cylinders off both sides at
the back and honed them and put new rings
on them, but otherwise that engine is untouched
from 1966 and runs smoother than almost
any other piston engine.  Everyone that flies
in it remarks on that.

But I've been flying it and maintaining it for
44 years now, which is not very long compared
to the honking, screeching and whining four-bars,
but it's been a pretty nice [url=[/url] for me.
Napoleon So Low
Posts: 49
Joined: Thu May 28, 2015 8:58 pm

[quote author=Colonel link=topic=232.msg703#msg703 date=1433942585]I guess I'm just not very smart, compared to you guys that tell me how stupid I am, all the time.[/quote]

C'mon Colonel, this is a different place, nobody's calling you stupid here. You don't need to post that.

Now, to the topic...

Please give us your thoughts on the proper way to prepare to start up an aircraft engine that's been sitting for longer than it should. I have such an engine. It's in an auto, but surely the same principles apply.

It's something I was meaning to ask you, but you disappeared suddenly.

Oh, and I haven't heard "lie like a rug" since my mom passed away, you are giving away your upbringing with that one!  :))



Colonel
Posts: 3450
Joined: Wed Apr 29, 2015 10:31 am

[quote]prepare to start up an aircraft engine that's been sitting for longer than it should[/quote]

As Larry King answered when asked what kind
of underwear he had on, "Depends".

Drain the engine oil and replace with new.

Remove dissicant spark plugs (if installed)
and remove dissicant and tape over intake
and exhaust (if installed).

You must remember that all the engine oil
has run off - you're looking at metal on metal
and that's very bad.

So, with the spark plugs out, crank the engine
over until oil pressure indicates.  Do not overheat
the starter motor.  With no compression it's life
should be pretty easy during this.

Recharge battery as required.

Clean and gap spark plugs and replace and torque.

Fuel as required.  If aircraft has been sitting a long
time, please drain out all the fuel and put fresh fuel
in it.  It will start much easier.

Off the top of my head, that's what I would do.  If
it's been sitting a very long time, replacement of
all engine and airframe hoses should be considered.

[quote]you disappeared suddenly[/quote]

[img][/img]
Napoleon So Low
Posts: 49
Joined: Thu May 28, 2015 8:58 pm

I was thinking maybe a squirt of some type of lubricant into the plug holes before cranking it, and disabling the fuel injectors so they can't shoot raw fuel into the cylinders. What do you think?
Colonel
Posts: 3450
Joined: Wed Apr 29, 2015 10:31 am

[quote]a squirt of some type of lubricant into the plug holes before cranking it[/quote]

Might better to do that before it
was stored.  When it comes time
to start it, oil in the cylinders is
just going to make [url= of blue[/url]
smoke.

[quote]disabling the fuel injectors[/quote]

Whatever it takes to not have fuel
get into the engine, while you are
cranking it with the plugs out, to
circulate the oil.
Napoleon So Low
Posts: 49
Joined: Thu May 28, 2015 8:58 pm

The other thing I was thinking about was putting a bit two-stroke oil in the fuel for better lubrication on first startup.

I do this with my small engine gadgets like lawn mowers and generators after they've sat around all winter.

I figure if 100/1 mix is good enough to protect an outboard motor that has no oil in thecrankcase, it's got to help somewhat when you first start a dry 4-stroke engine.

How long do you think it takes after you park an engine before the cylinder walls and valve train dry out?
David MacRay
Posts: 1259
Joined: Wed Jun 03, 2015 3:00 pm

[quote author=Colonel link=topic=232.msg720#msg720 date=1433965011]
[quote]a squirt of some type of lubricant into the plug holes before cranking it[/quote]

Might better to do that before it
was stored.  When it comes time
to start it, oil in the cylinders is
just going to make [url= of blue[/url]
smoke.


[/quote]
What about Sea Foam?

I would think WD-40 would not make much smoke and it has quite a bit of solvent. I don't think it burns either so maybe too much would not be good. Then again it seems to go away pretty quick. Do that before changing the oil?

My father used to pour this http://rislone.ca/product/engine-treatment/ down the carburetor of his running vehicles sometimes. It makes smoke but he believed it stopped valves from sticking too.
Colonel
Posts: 3450
Joined: Wed Apr 29, 2015 10:31 am

Too bad Mike Busch isn't here!  I know
the AME's hate him, but gosh, he knows
his stuff.

I could write a book about sticking valves
(Lyc SB 388B and SI1425A and dental floss)
but I'm sure the four-bars would crap on
me from a great height for trying to help
people, so screw it.

I am not a fan of Rotax engines in airplanes,
but perhaps I've led a sheltered life. 

Nobody uses Franklin engines any more,
except for a few antiques.  I see more
Kinners on the field than Franklins - the
company was purchased some decades
back by a company in Poland or someplace
like that.  I have no idea as to parts
availability, which would be crucial.  If
you can't get parts, it's all over.  Not
sure if any engine shop in Canada will
even work on them.  If not, what do
you do when it's time to overhaul?

Never flown behind a Jacobs.  Again, I
have no idea if you can get parts for it,
or if anyone will still overhaul them.

And good luck trying to find an AME
whom is willing to work on anything
weird like this.  They won't even
touch geared engines any more.  I
remember we had a simple problem
with a GO-480 in the T-bone a few
years back and all the AME's scattered
like cockroaches when you turn the
light on.

Before you consider an airframe with
a whacky and wild engine, first find an
AME that is willing to work on it.  Not
easy.

PS  Seafoam is magical.  It dissolves
varnish deposits from mogas in motorcycles
and other small engines that didn't have
that red fuel stabilizer added to it.  Seafoam
is actually a better fuel stablizer than the
red stuff.  Never used it on an airplane -
never had to.  100LL doesn't turn cloudy
and deposit varnish like mogas.  Seafoam
has a solvent in it like acetone or toluene
or something like that.  Hell, I've seen
people pour a gallon of lacquer thinner
into their car gas tanks - it's one heluva
nasty solvent.
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