Cherokee questions

[Chairboy]

I've found an interesting looking plane on Barnstormers, and I'd like to take advantage of the experience here to get some perspective on this and get a sanity check.

http://www.barnstormers.com/classified_163113_+1979++PA-28-161.html

First off:
The engine is run out.  My thought was to get the data on compression, oil consumption, static RPM, and whether or not he's done any oil analysis.  Based off that, I'd be able to determine if the engine would be fine now, but I'd be budgeting for an overhaul in the near future.

I'll get a copy of the March 07 annual if, after talking with him today, I want to pursue this.  Knowing that it's only part of the story (for instance, is the A&P his neighbor who just rubber stamps it, or is there some evidence that a spar or tail AD is about to come due?)

What I'd like from y'all is:
1. Feedback if my assumptions above sound reasonable, and if I'm missing anything.
2. Ideas for other things to check/ask about before heading out to visit the guy.
3. Warning signs to look for.

Thanks!

[Maverick]

Getting a copy of the annual isn't going to do anything for you. If the IA (IA's approve inspections in aircraft not A&P's) is rubber stamping the annual, the docs will not give you a clue about it. You need to have an independent AI do an annual or 100 hour on it to determine if the AD's are really complied with. Some can be seen as mods performed and parts numbers checked or work observed. Others can't be seen as they are repetitive inspections.

In short you need the logs and the aircraft for the IA to look at. This will not be cheap. Do NOT take the owner or his own mechanic's word for it, get it checked and a detailed inspection is the only way to determine if the AD's are done and done properly for certain. You can do an abrieviated look and take your chances otherwise as I imagine most new owners do.

If there are no oil analysis records getting one now won't help all that much unless the engine is making metal in fair quantities. That would mean an immediate overhaul or exchange.

If you have an IA that you are friendly with you can get a quick and dirty checklist from him to look at including a list of critical (expensive) AD's to look for in the logs. Again that's not proof, just log entries.

Ask about taking the aircraft to an independent IA for a look over. If the owner objects walk away.

Look for signs of corrosion in seams, bends and along areas that water will gather. Pull off the wingtips and look inside of the wings for broken, cracked, or bent ribs. Any fuel leaks from the tanks on the underside. How much fuel dye is there? A trace is no big deal, a large or dark stain is a sign of a leaking tank and sealing the tanks is a bear on the Cherokee. Look at the fuel lines and hydraulic lines. Are they hard and brittle?

Are the brakes smooth in application? Look at the disks for rust and pits. Light surface rust is OK but bad pitting, warps and deep grooves is a sign of poor maintenance. Does the parking brake hold?

Look inside the cowling for old burned on oil (old continuing leak). Are there signs of sloppy or ammature work like cheap hollow pop rivets instead of cherry max rivets or crude patches. Look at the back of the engine, are the mags the same or has one been changed recently and they look very different. Is the engine compartment area clean or full of rats nests, black electrical tape, broken wires. If it is sanitary in there it may have been steam cleaned to hide an oil leak. Old engines leak so expect to see some dirt and a little oil as well as silicone sealant on the case seams. Look at the bottom of the plane for oil stains streaming from the exhaust. Lots of oil equals bad rings and or valve guides.

Pull plugs to see if the cylinders are running uniform. Any oily plugs on the top? Expect the bottom ones to be a little oily but if it fills the plug and or drips out that's severe fouling. Look at the plug wires for condition and security. Are they loose and flopping all over the place. Does one mag have a new set of wires and the other one an older set? Do a compression check and use an independent compression guage, not the owners.

Does the engine start in a couple blades or does it grind on and on before starting rough. Does it run smooth quickly or pop and belch for an extended time.

Battery compartment, clean or corroded up badly. Cables, smooth or rusted and fraying?

There's lots to look at and your $ ahead to have your own mechanic look the bird over. Hope this helps some.

[Chairboy]

Great advice!  I'd plan to have an independent check first no matter what if I decided to buy it, I was just thinking of things to check at this stage where I'm trying to figure out if I want to make the $$$ investment in checking it out.

I'll talk to the guy today and feel him out on the independent IA, if he has any probs with it, then we're done, like you said.

Thanks!  I'll report back any progress here if anyone is interested.

[Wolfala]

Talking a couple of items here. Engine is 365 past TBO. Would be interested to see what the oil consumption is at. Also what the oil analysis records are (if the previous owner has done any oil analysis looking for metal and other goodies). What was the Cherokee used for? If it was just a Cross Country bird that 300 past TBO is certainly doable if not expected. Stable temps for hours on end with 1 power change at takeoff and 1 for descent.

I dunno, are you looking for a paste and glue special? If so, why not get a Grumman T-Cat. Has the same engine as the PA-28-161 but is a lot more fun - and this 1 is with a new engine at 150HP instead of 115.

http://www.aso.com/i.aso3/aircraft_view.jsp?aircraft_id=100047&return_url=/i.aso3/search.jspyyyyyiaso3sid=1xxxxxtypeid=1xxxxxsearchid=11315450xxxxxregionid=-1xxxxxmode=xxxxxtypeid=1xxxxxmmgid=31xxxxxmodelgroup=falsexxxxxsearchid=11315450xxxxxregionid=-1



And for all intents, it'll go the same speed at the PA-28-161 but burn a little less fuel.

Hell, try to find a Grumman Tiger for 10k more or 1 with a run out engine - point is, you can do better then a PA-28 of any type.

For instance, a Grumman Traveler. Same engine as the PA-28-161.
http://www.aso.com/i.aso3/aircraft_view.jsp?aircraft_id=106307&return_url=/i.aso3/search.jspyyyyyiaso3sid=1xxxxxtypeid=1xxxxxsearchid=11326594xxxxxregionid=-1xxxxxmode=xxxxxtypeid=1xxxxxmmgid=31xxxxxmodelgroup=falsexxxxxsearchid=11326594xxxxxregionid=-1

But does a honest 125 and still 1500 remaining on the engine.
$36k isnt bad



Wolf

[Chairboy]

Called the guy, had a good conversation.  There was one thing that caught my attention, but in general it was pretty positive.
- He's an A&P/IA, so I'm assuming he did the annual.  Definately want to get a second opinion if I go to buy it.  He's bought a few planes, put time into them, and re-sold them, that's the backstory to this one.
- The lowest compression is 68
- He's seeing about 4ish hours per quart.  There's no oil/air separator, so that sounds pretty reasonable.
- It generates about 2325 static on a pretty standard day.
- It was a trainer for about 4000 hours earlier on in its life, recently it sat for a couple years.
- It's flown about 7 hours since, and he's going to put a few more on it before he sells it.
- He popped the plug out of the front of the crank to check for the pitting AD, and it was immaculate.  That's probably a good sign about the environment it was stored in.
- He's fixed a few squawks, like replacing a leaking primer line.
- He's examined the attach point on the rear spar carry through (one of the fatigue/corrosion points) and it was fine.
- He says the inside of the wings look good.  No damage, and he'd say they're an 8/10 on corrosion.  I'll clarify what he means by that, I'd assume that just means the usual surface stuff that any metal structure would get.  Thoughts?

So all in all, interesting.  I highlighted the part that really got my attention, but if the plane has 10 hours on it since and a pair of thorough mechanical inspections (him and then my hired gun), then that might be ok.

[Wolfala]

Chair,

Here is my thing. You got 29K on an airplane with a worn out engine. OK, so an engine will run, in the IO-320 range a minimum $15,000 + installation. Point is, look at the Grumman, 7K more - but has an engine with 1500 left on it, is faster, hasn't been sitting idle for 7 years.

Point i'm making, unless something in that engine or airframe was preserved under the engine manufactures specs and Piper's specs - something is gonna time bomb and its not gonna be cheap. And i'd much rather see you in a plane that has been flown at minimum once a month then something sitting idle for 7 years.

Call me 4083487058 and we'll jam.

Wolf

[Chairboy]

I'll call later, but I think you transposed the "7 hours flown since" with "sat for a couple years".  

[Wolfala]

Originally posted by Chairboy
I'll call later, but I think you transposed the "7 hours flown since" with "sat for a couple years".  

I read it as he got it while it was sitting for 7 years idle. Then he flew it for 7 hours before running into you.

[Maverick]

I would be concerned about it's use as a trainer.  Since it would have been as a basic trainer the landing gear would have taken a pounding.

What did you mean by this? "- It generates about 2325 static on a pretty standard day."

A 68 compression is good but again don't take it at face value.

The crank plug is a recurring check IIRC.

An over run engine is not something that mandates overhaul as TBO is a recommendation and not mandatory for private aircraft. As long as it's holding compression and not making metal you should be OK for as much as 1000 hours over TBO. Make sure there are no other outstanding crank AD's, some of Lycoming's cranks ended up being the subject of a mandatory replacement.

Does the engine have a filter or does it use an oil screen?

I'd agree on your assumption regarding corrosion. An 8 out of 10 would be minimal corrosion. ALL of the older aircraft have some, it's a natural process and you have to stay on top of it.

[Chairboy]

Originally posted by Wolfala
I read it as he got it while it was sitting for 7 years idle. Then he flew it for 7 hours before running into you.

Roger that, no, it sat for about two years and has had 7 hours put on it since.  He bought the plane, did work on it, inspected it, and has started flying it to find squawks.

[Wolfala]

Same rules apply my friend, whether 2 years or 7 years. Oil does not sit attached to engine parts when idle for more then 1 month. If you are in a coastal area, get it bore scoped - probably run the engine and have rust come out of the oil for 10-20 hours before stuff starts looking normal. Even though its an old engine - point is, sitting idle is sitting idle unless the aircraft and the engine were preserved per the Aircraft Maintenance Manual and Engine Manual instructions and not left to sit out with no preparation.

[Chairboy]

Good points, thanks.  I'll follow up on that, he mentioned borescope, but I didn't catch if he said he _had_ checked with one or hadn't.  The engine was run while it was sitting, but that can introduce new problems even while it solves others.  If it was getting started and run for 30 seconds every so often, that's probably worse than just sitting (from a corrosion standpoint) if I understand right, and that the engine really needs to spend a few minutes at high power to take care of condensation and acids and whatnot.

[Wolfala]

This is a perfect example on Controller.com

http://www.controller.com/listings/forsale/detail.asp?OHID=1111020&guid=668FE770D8B8439BBC25EF1C73BCCA36

Lancair Legacy - for most eyes it looks like a cherry deal. Guy builds it, test flies it for 32 hours and then suddenly dies of a massive heart attack. The plane sits in his estate idle from November 2005 up until the current day. Hasn't even finished its test flight phases yet.

The guy who inherited the plane didn't do any preservation of any sort for the engine. The oil, is the EXACT same oil as they put in when they bench ran the engine back in 2005. It was never drained. It has never been run since 2005. That engine, at $55,000 is trashed. Even with 30 hours on it. And he wants 200K for it.

http://home.earthlink.net/~gatschetb/

[Maverick]

What part of the country is this bird in or was stored in? Aircraft engines don't develop the same problems in say Southern AZ. as they would in Florida. If it was in dry country I wouldn't be quite so concerned with internal engine rust. Sitting would be equivalent to flying a 100 hours in actual wear so it does deteriorate somewhat.

[Wolfala]

Bakersfield, CA

Not the driest place on the planet.