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View Full Version : To overhaul or not to Overhaul, that is the question-


EridanMan
May 9th 06, 01:12 AM
I've had an opportunity recently to purchase a Piper PA28-140- absolute
creme puff cosmetically... but the problem (and reason for the good
cosmetic condition) is that the plane has been sitting in an
enironmentally stable (dry, 50-80 degree ambient temperature) for
almost a decade now.

(For those who responded to my other post, I know this is a huge step
down from what I was looking for, but It would just serve as a
timebuilding local puddlejumper/toy for a few years until I can afford
something better, and at the price, I'm garanteed not to loose anything
on depreciation)

The purchase is for a _very_ good price.

Before she went into the hanger, the ship had 300 hours on a rebuilt
engine (2300 hours TTAF).

I'm getting wildly varying advice from shops. The one shop whose
actually seen her has been assuring me that considering the condition
of storage and the good condition before she went in, He's reasonably
sure (and he's going to confirm/deny with a prepurchase this week) that
all she'll need is to have all of her seals replaced, as well as a good
prelubrication job done. He said that as long as I go through and make
sure that the engine is well lubricated and sealed before I turn it
over even once, then there really shouldn't be any damage worthy of a
rebuild.

The other shop, the one who I have more experience and tend to trust
more (although they tend to be very by-the-book and high-end) has
_adamantly_ insisted that If I get the plane, she will need a full
engine rebuild. They said that even if she hadn't been static for 10
years, Lycoming insists that all O320's be rebuilt at 2000 hours OR 10
years.

Both shops agree about the rest of the necessary work (Avionics, new
struts, new tires, new seatbelts, etc). The only place they disagree
is the engine.

I'm not sure what to think... On one hand I agree, err on the side of
safety. On the other hand, everything I know about engines suggests
that as long as A- there was no opportunity for the introduction of
moisture and B- the engine is fully lubricated/sealed before running,
engine corrosion/wear shouldn't be an issue.

I'd love to hear some of your takes on the situation.

EridanMan
May 9th 06, 01:14 AM
Type correction - she's been sitting in an environmentally stable
_hanger_

Dan Luke
May 9th 06, 01:34 AM
"EridanMan" wrote:

> The other shop, the one who I have more experience and tend to trust
> more (although they tend to be very by-the-book and high-end) has
> _adamantly_ insisted that If I get the plane, she will need a full
> engine rebuild. They said that even if she hadn't been static for 10
> years, Lycoming insists that all O320's be rebuilt at 2000 hours OR 10
> years.

They are being unreasonable. Lycoming *recommends* that all O320's be
rebuilt at 2000 hours OR 10 years. It's not cast in stone for a private
owner. My Lyc. O-360 had 2700 hours SMOH when I had it overhauled; it could
easily have gone more.

> Both shops agree about the rest of the necessary work (Avionics, new
> struts, new tires, new seatbelts, etc). The only place they disagree
> is the engine.
>
> I'm not sure what to think... On one hand I agree, err on the side of
> safety. On the other hand, everything I know about engines suggests
> that as long as A- there was no opportunity for the introduction of
> moisture and B- the engine is fully lubricated/sealed before running,
> engine corrosion/wear shouldn't be an issue.

Maybe. I'd still worry about the camshaft. Lyc. cam's are notorious for
rusting from disuse. Why not have it opened up and looked at?

--
Dan
C172RG at BFM

nrp
May 9th 06, 01:58 AM
My call -
I think it depends on how it was shut down last. Has it had reasonable
oil change intervals before shut down? Has it been fed a lot of 100LL?
Has it been stored under high humidity conditions? Why replace seals?

All are possible considerations but none are necessarily deal killers
in my book. Pull the plugs and do a visual inspection of the cylinders
with a small light dropped thru the opposite plug holes. Assuming it
looks reasonable, change the oil, drain the fuel & the carb bowl,
preheat the crankcase so the startup oil is warm, and go for it.

This engine is closer to being bullet proof than any other. Cam
failure due to corrosion might be a problem so I would check the oil
screens & immediately get an oil analysis sample after a short first
flight.

I have a 172M that at 31 years & 1700 hrs since new still doesn't use
oil between changes. If it did or had any other negative symptoms, I'd
be overhauling it. It never sat for more than a couple of months at a
time though.

I'm sure others will have an opposite opinion. Let us know what you do
& how it turns out. Good luck!

Doug
May 9th 06, 03:02 AM
No way to tell for sure. What I would do is go ahead and treat it like
I was going to run with what I got, and see how it goes. After a few
hours of running do a compression test and monitor oil usage. If all is
well, run it till it starts giving oil burn, low compression, power
loss or metal in filter. THEN rebuild. You might get 1000 or more hours
out of it. But as I said, no way to tell for sure.

Kyle Boatright
May 9th 06, 03:09 AM
"EridanMan" > wrote in message
oups.com...
> I've had an opportunity recently to purchase a Piper PA28-140- absolute
> creme puff cosmetically... but the problem (and reason for the good
> cosmetic condition) is that the plane has been sitting in an
> enironmentally stable (dry, 50-80 degree ambient temperature) for
> almost a decade now.

If it has been sitting 10 years, my guess is that the engine will have rust,
unless it was in an extremely low humidity climate.

Pull a cylinder or two, look at the cylinders, look at the cam, and make a
decision. Pulling the cylinders shouldn't cost a whole lot. A good mechanic
can pull one off and reinstall it in a couple of hours. For someone like
me, it take a bit longer... ;-)

In addition, if the airplane has truly been sitting that long, my guess is
that most of the hydraulic seals will be questionable. Brake cylinders and
the nosewheel strut are the obvious areas for potential trouble.

Maybe the price you're getting *is* incredible, but it is often cheaper to
buy a nice example of the plane you want than to buy a marginal example and
bring it up to nice standards.

KB

May 9th 06, 06:05 AM
EridanMan > wrote:
> I've had an opportunity recently to purchase a Piper PA28-140- absolute
> creme puff cosmetically... but the problem (and reason for the good
> cosmetic condition) is that the plane has been sitting in an
> enironmentally stable (dry, 50-80 degree ambient temperature) for
> almost a decade now.

<snip rest>

Anything sitting that long should be highly suspect and throughly
inspected before you bet your life on it.

All the "rubber" parts are almost assuredly dried out, ready to
fail, and in need of replacement, and in the case of an aircraft,
the ones in the fuel system and brake system could cause you to
become the occupant of a smoking crater.

Depending on what was done before it was parked and the environment
since, the engine (other that the "rubber" parts) could be in pristine
condition or ready to fail at any second.

What is your life worth to you?

In another life I did a lot of sports cars of dubious quality which
sat for a long time with varied results when fired up.

There is a big difference between an engine failure on an old stored
car engine and an old stored aircraft engine when you are looking for
a place to park it when it fails in service.

--
Jim Pennino

Remove .spam.sux to reply.

Thomas Borchert
May 9th 06, 08:22 AM
EridanMan,

> Lycoming insists that all O320's be rebuilt at 2000 hours OR 10
> years.
>

for Part 91?

You omitted an important detail: Was the engine put in long-term
storage condition, including the oil that goes with that?

Also, wouldn't a borescope inspection answer some of the questions? And
how it runs at the first try? And oil analysis? IN any case, a
categoric rebuild seems unnecessary.

However, with all the other things you mention (seals, avionics,
interior), I really have to wonder how this can be a good deal.

--
Thomas Borchert (EDDH)

May 9th 06, 12:57 PM
: The purchase is for a _very_ good price.

What you are describing is almost completely the same situation as the plane
that we bought coming up on 4 years ago. It was a PA28-140 with a -180 engine in
it... only 5 hours since overhauled, but 8 years earlier. It didn't have an interior
or any avionics, but the price was really good.

We bought it anyway, and then discovered that not only was there no time on
the engine, it wasn't even broken in! It had chrome cylinders (notoriouly difficult
to break in), and I put 50 hours or so on it burning a quart every 4-5 hours or so.
There were two "soft" cylinders pulling it through. Between that and some "morning
sickness" and power losses indicating sticking valves, we pulled the jugs and had them
IRAN'd. I took a good look at the cam with them off and didn't see any evidence of
spalling, pitting, or rusting.

Since then, I've installed a full digital IFR stack, earned an instrument
rating with it, put in an interior, and flew it to Alaska and back (among other things
with the 500 hours we've put on it).

In short, take the advice of expecting large-ish repairs in the short-term.
In our case, I (probably mistakenly) thought that we were buying a "fixer-upper," but
at least it was mechanically sound and flyable immediately. I developed a good
repoire with my mechanic, and did all the avionics installations myself from used
equipment... so from nothing to King digital IFR stack was less than $5k. That's not
normal. To have done it the "normal" way, the same stack would probably have cost
$15k to buy and have installed.

Interior was the same... cost $1200 and a few weeks' worth of my time doing
prep work and doing the install after the upholstery shop made up the panels and
recovered the seats.

Other maintenance has been fairly "normal." In short, I guess I'm saying you
may get off OK, but you may need to do some big work. If you're mechanically inclined
and have a mechanic you can work with, you could get by inexpensively. If you have to
have all the work done, it'll likely cost you more than it's worth. If the top end
needs work like ours does, it isn't too bad. If the cam is rusted and spalled, you
gotta split the cases which is a good fraction of the labor for a full overhaul.

-Cory


--

************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

EridanMan
May 10th 06, 01:07 AM
I'm a mechanically inclined type, and this is _exactly_ my plan.

I'm looking for a solid, corrosion free 'base' to start building up a
plane... Think of it as 'experimental aviation light'- I don't want to
wait 3000 hours to start flying, but I don't mind a plane that's going
to take some elbow-grease along with the purchase price.

The low time airframe and complete lack of corrosion are two huge
pluses. It also seems like there is quite a cult following for the old
Hershey-wing Pipers, aerodynamic modifications are plentiful and
inexpensive (how useful they are remains to be seen of course), but I
still like the idea.

The ship is going to need an IFR stack (currently VFR only, and
eventually I want my IFR ticket), but as you said, King IFR stacks are
amazingly cheap right now (I guess everyone is dumping them in the rush
to glass, a trend that will only accellerate IMHO).

I got a chance to get my elbows dirty yesterday in the plane (before
hand I was dealing with world of mouth from a friend, the plane is
being sold by an aquaintance of sed friend).

The wings and sheetmetal was pristine (original stenciling still
clearly visible, you could probably eat of the wing spar metal, etc).
interior was a mixed bag, plastics are all flawless, but the panel is
in sorry shape and the plane doesn't even have an intercom (previous
owner used speaker+handheld). Seats Rails were flawless (and all seat
adjustments), but the seats themselves need re-upulstering (and the
arm-rests were all cracking and showing their internal foam).

The only real 'ugly' I came across was the Fuel tanks... red goo in
both. I'm already pricing salvage replacement tanks and fuel system.

I'm amazed how simple the plane is... the entire fuel system looks well
within my mechanical abilities (and the parts don't seem to be too
bad). I did confirm that the fuel tank, while ugly inside, did not
leak within the wing (one of my concerns).

I'd also probably do the interior work myself (within legality in
regards to the panel, of course).

I'm having a mechanic go over her tomorrow to find anything I missed in
my rather thorough inspection... assuming there aren't any
showstoppers, I'm ready to put down a deposit.

My final determination came down to one simple equasion... Purchase
price + Engine Overhaul < Value of comparible planes on barnstormers...

What else can I say?

EridanMan
May 10th 06, 01:21 AM
OH, going on the 'I'm getting her as a fun project' thing...

Does anyone know anything about kits or instructions to modify the
PA28-140 to electric trim (I know the Cherokee STC for electric trim
covers the Cherokee 140, but that's about as much as google searching
online has taught me)? About my only complaint with the older hershey
Cherokees is the roof mounted trim lever, this is going to be a very
early project.

May 10th 06, 12:37 PM
EridanMan > wrote:
: I'm a mechanically inclined type, and this is _exactly_ my plan.

If your mechanic is OK with you doing a lot of work like that, you should be
able to pull it off.

: I'm looking for a solid, corrosion free 'base' to start building up a
: plane... Think of it as 'experimental aviation light'- I don't want to
: wait 3000 hours to start flying, but I don't mind a plane that's going
: to take some elbow-grease along with the purchase price.

Same boat here... I just wanted something that was in flyable condition while
I worked on it. Two weeks after I brought it home and a week after my PP checkride, I
flew mine to Ohio (approx 200nm) to see my sister. Nothing but my new handheld
NAV/COM and a borrowed handheld GPS.... and I debated as to whether or not I needed
the latter.

: The low time airframe and complete lack of corrosion are two huge
: pluses. It also seems like there is quite a cult following for the old
: Hershey-wing Pipers, aerodynamic modifications are plentiful and
: inexpensive (how useful they are remains to be seen of course), but I
: still like the idea.

Some of the mods are worth it, some less so. You didn't say the year of the
bird (standard T-layout makes it '69 or newer like mine... older had shotgun-blast
panel)

: The ship is going to need an IFR stack (currently VFR only, and
: eventually I want my IFR ticket), but as you said, King IFR stacks are
: amazingly cheap right now (I guess everyone is dumping them in the rush
: to glass, a trend that will only accellerate IMHO).

Old-school IFR (in my case, DME, VOR-DME RNAV, ILS, and VFR-GPS/COM) is a good
bargain... especially the RNAV.

Of course I just found out yesterday that my transponder and extra slide-in
transponder are both TU.

: I got a chance to get my elbows dirty yesterday in the plane (before
: hand I was dealing with world of mouth from a friend, the plane is
: being sold by an aquaintance of sed friend).

: The wings and sheetmetal was pristine (original stenciling still
: clearly visible, you could probably eat of the wing spar metal, etc).
: interior was a mixed bag, plastics are all flawless, but the panel is
: in sorry shape and the plane doesn't even have an intercom (previous
: owner used speaker+handheld). Seats Rails were flawless (and all seat
: adjustments), but the seats themselves need re-upulstering (and the
: arm-rests were all cracking and showing their internal foam).

Check for corrosion on the trailing edges of the wings under the flaps. Also
way up behind the panel and under the carpet by the door. Lots of leaks in PA-28's.

: The only real 'ugly' I came across was the Fuel tanks... red goo in
: both. I'm already pricing salvage replacement tanks and fuel system.

Technically speaking, tanks cannot be replaced except with new. The holes are
drilled individually for every plane. The fuel tank is of course a structural part of
the wing, so they're kinda important.

: I'm amazed how simple the plane is... the entire fuel system looks well
: within my mechanical abilities (and the parts don't seem to be too
: bad). I did confirm that the fuel tank, while ugly inside, did not
: leak within the wing (one of my concerns).

: I'd also probably do the interior work myself (within legality in
: regards to the panel, of course).

: I'm having a mechanic go over her tomorrow to find anything I missed in
: my rather thorough inspection... assuming there aren't any
: showstoppers, I'm ready to put down a deposit.

: My final determination came down to one simple equasion... Purchase
: price + Engine Overhaul < Value of comparible planes on barnstormers...

: What else can I say?

Of course pull the prop through and feel the compression. Borescope wouldn't
be a bad idea if you're so equipped. Engine-wise, you could also pull off the valve
covers and put a dial indicator on the pushrods to measure the cam lift. If it hasn't
flown at all in the long time however, it might take a few hours of flying before
rusting/pitting of a corroded cam would show up as spalling and loss of lift.

-Cory

--

************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

Jay Masino
May 10th 06, 02:00 PM
EridanMan > wrote:
> Does anyone know anything about kits or instructions to modify the
> PA28-140 to electric trim (I know the Cherokee STC for electric trim
> covers the Cherokee 140, but that's about as much as google searching
> online has taught me)? About my only complaint with the older hershey
> Cherokees is the roof mounted trim lever, this is going to be a very
> early project.
>

I don't know if it's included on my equipment list as an option, but you might
be able to add it by just finding the original equipment parts. I'm not sure
I'd bother though. The overhead trim is REAL easy to get use to, and in my
experience, is much lighter to move than the between the seats trim. In short
order you'll be reaching up and spinning it one way or the other with your index
finger. It's nice.

--- Jay

--

Jay Masino
http://www.JayMasino.com
http://www.OceanCityAirport.com
http://www.oc-Adolfos.com

May 10th 06, 02:38 PM
Jay Masino > wrote:
: I don't know if it's included on my equipment list as an option, but you might
: be able to add it by just finding the original equipment parts. I'm not sure
: I'd bother though. The overhead trim is REAL easy to get use to, and in my
: experience, is much lighter to move than the between the seats trim. In short
: order you'll be reaching up and spinning it one way or the other with your index
: finger. It's nice.

: --- Jay

That's what I was trying to say with my previous post. It's not that bad to
get used to. I doubt it'd be easy to retrofit to floor-mounted trim, and I'm sure
electric is either impossible or really pricey.

Given that you've got a project plane, that modification should be at the very
very bottom of an already long list IMO.

-Cory

--

************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

EridanMan
May 10th 06, 06:58 PM
Cory,

Thank you for all the feedback, its nice to talk to someone whose been
down the path I'm about to commit too.

Is there a good online owners group that you would recommend?

The engine is going to go under borescope today. Also - I did notice
what I would consider 'normal to light' levels of corrosion underneath
the interior trim immediately in front of the door (I've seen this
corrosion in virtually every plane I've looked at, and what I did see
was just superficial surface stuff). Shining a lite through the dash,
I could also see what looked like a bit of corrosion underneath where
the windscreen intersects the fuselage - I wasn't able to get a good
look- but I've leat the FBO whose doing the pre-purchase know its there
and that I'm concerned about it.

I did not look at the rear wing near the flaps (although, fwiw, the
flaps were the absolute smoothest 'buttery' motion I've ever seen in
any piper, the mechanism felt brand new, and there was practically no
play in either flap.

I didn't realize that the fuel tanks weren't swappable parts... The
FBO says that they know a shop where we can send off both tanks to be
reconditioned and resealed for ~5-600 each, might just take that route.

As far as aerodynamic mods, any thoughts on the 2550 dollar package
provided by pipermods.com? It includes wingtips, wing seals, vortex
generators, stabilator tips, Prop tip mod (The ship's prop is brand new
and absolutely flawless) and prop repitching.

Beyond that, all I'd want to do (eventually, not initially) is high
performance wheel pants and a powerflow exhaust... But all in good
time.

May 10th 06, 07:30 PM
: As far as aerodynamic mods, any thoughts on the 2550 dollar package
: provided by pipermods.com? It includes wingtips, wing seals, vortex
: generators, stabilator tips, Prop tip mod (The ship's prop is brand new
: and absolutely flawless) and prop repitching.

I don't know about all of them, but I can say that the AMR&D VG's work well.
Wingtips (whether Hoerner-style or droop-tip "Batwing" tips) help reduce sink.
Prop-tip mods supposed to help a little, along with the exhaust. The other ones I'm
not too excited about.

If you're thinking of autogas, you cannot run high-compression unless you've
got the clamshell cowling and buy the Petersen STC.

: Beyond that, all I'd want to do (eventually, not initially) is high
: performance wheel pants and a powerflow exhaust... But all in good
: time.

Make it go first... then worry about mods. :)

-Cory

--

************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

Ray Andraka
May 10th 06, 09:46 PM
EridanMan wrote:

>
> The only real 'ugly' I came across was the Fuel tanks... red goo in
> both. I'm already pricing salvage replacement tanks and fuel system.
>

Used tanks off another airplane probably won't fit. The piper tanks are
trimmed and drilled by hand and will only fit the airplane they were
trimmed and drilled for. If you replace them, you'll have either
replace the whole wing, or get new tanks from piper (and then trim and
drill them yourself). A better option would be to send the tanks out to
one of the two shops that do tank resealing and have them disassemble,
clean-out and reseal the tanks. You'll have to repaint them when you
get them back, as part of the process strips the paint. The cost is
around $600/tank. Call one of those shops and discuss your situation
with them. Skycraft used to do it, but I think they sold their tank
resealing business. I don't recall the name of the company that took it
over, nor the name of the other company. You could also have your local
mechanic do it if he is good with sheet metal, but you may end up paying
more.

It may also be possible to use a solvent to clean the goo out of the
tanks. Worst that would happen is it might also take out the sealant
and make it necessary to get the tanks resealed.

May 11th 06, 02:27 AM
On Wed, 10 May 2006 16:46:56 -0400, Ray Andraka >
wrote:


>Used tanks off another airplane probably won't fit. The piper tanks are
>trimmed and drilled by hand and will only fit the airplane they were
>trimmed and drilled for. If you replace them, you'll have either
>replace the whole wing, or get new tanks from piper (and then trim and
>drill them yourself). A better option would be to send the tanks out to
>one of the two shops that do tank resealing and have them disassemble,
>clean-out and reseal the tanks. You'll have to repaint them when you
>get them back, as part of the process strips the paint. The cost is
>around $600/tank. Call one of those shops and discuss your situation
>with them. Skycraft used to do it, but I think they sold their tank
>resealing business. I don't recall the name of the company that took it
>over, nor the name of the other company. You could also have your local
>mechanic do it if he is good with sheet metal, but you may end up paying
>more.
>
>It may also be possible to use a solvent to clean the goo out of the
>tanks. Worst that would happen is it might also take out the sealant
>and make it necessary to get the tanks resealed.

Sending the tanks out for a skycraft type rebuild is a no-brainer. You
do it once, and they will likely last forever.

Not sure what age this particular aircraft is, but finding old
Cherokee's with sloshed tanks used to be quite common.

TC

May 11th 06, 02:27 AM
On 9 May 2006 17:07:48 -0700, "EridanMan" >
wrote:

snip

>The wings and sheetmetal was pristine (original stenciling still
>clearly visible, you could probably eat of the wing spar metal, etc).
>interior was a mixed bag, plastics are all flawless, but the panel is
>in sorry shape and the plane doesn't even have an intercom (previous
>owner used speaker+handheld). Seats Rails were flawless (and all seat
>adjustments), but the seats themselves need re-upulstering (and the
>arm-rests were all cracking and showing their internal foam).

snip

Have seen Cherokee's that looked like mirrors inside the wings, have
also seem them white & flakey.

You need to take a good look at all the steel fittings. They were
never really properly painted/protected from new, and can get really
ugly.

Others have made fuel tank suggestions. Having gunk in the tanks is
not uncommon.

TC

Steve Foley
May 12th 06, 11:58 PM
> wrote in message

> Sending the tanks out for a skycraft type rebuild is a no-brainer. You
> do it once, and they will likely last forever.


Not forever. Mine were done by Skycraft in 1986, and again in 2005. (I guess
he marks them)

Does anyone have a pirep on the new owners? I hear he sold it and the new
operation is in NY. It was in a T-hangar in Hampton, NH

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