Engine not run for 3 years 0-320

[cap41]

I am considering a PA-28. The plane has not flown in 3 years. It will have an annual done with purchase.

What should we be worried about with the engine. owner said he ran the engine a few times a year. But, there is nothing in the logs to indicate.

What extra inspection should we consider doing to the engine or airframe. Engine is 17 years and 459 hours SMOH.

[TeePeeCreeper]

17 years and under 500 hours... That's a lot of time sitting around not flying!

Best case senario, that little engine doesn't make metal and clog the screen. -Consider yourself lucky.

Worse case senario, after 50 hours (post purchase) you're all in for a complete overhaul...


If your serious about buying this particular aircraft, I would negotiate around the aforementioned "worse case senario".

All the best,
TPC

[I_Drive_Planes]

Bruce Dickinson of Iron Maiden is an accomplished pilot and he has some really good advice for you regarding this airplane:



3 years is quite a long time for an airplane to sit and rot. Lycoming engines are known both for their ability to take the abuse of hamfisted students and for their intolerance for inactivity. This airplane has been sitting for quite a while, and 459 hours in 17 years doesn't indicate regular use through its lifetime. I'm also guessing that the engine was not preserved properly for storage.

What should we be worried about with the engine. owner said he ran the engine a few times a year.

That is not good. When you run an engine all sorts of nastiness accumulates in the oil that accelerates internal corrosion. This stuff is burned off on flights of an hour or more with the oil at full operating temperature. Ground running a parked airplane occasionally is very detrimental to the engine.

There are lots of Cherokees on the market, find one that someone loved and has flown the hell out of (that's what I did!). You will get far more life out of an airplane that is at 2000 smoh and flies 200 hours a year than a low time airplane that has been parked for an extended period of time.

Airplanes that are flown a lot tend to be in much better mechanical condition than those that spend most of their lives sitting. I'd be very concerned about other aspects of a sitting airplane's mechanical condition beyond the engine as well.

[cap41]

Thanks for the advice!

[Heliian]

You can consider that engine non airworthy and should have it overhauled, nay, exchanged for an oh'd unit that is up to date. I can't imagine what kind of surprises that old anchor holds. NOT WORTH THE RISK.

[cgzro]

I would assume a complete overhaul in next year with quite possibly non usable crank/cam etc.
So the core exchange value is even lower and needs to be factored in.

[2R]

Find an AME that is familiar with that model aircraft and PAY for a pre purchase inspection.
The money spent will save you a lot of money and grief.

[DanWEC]

Not to get on a different topic, but what is it about an aircraft engine that makes it so intolerant of sitting to the point where it might totally fail in a few dozen hours? I've never quite understood this.
Any car engine with the equivalent of a few thousand hours on it would be essentially "ok" if it sat for 3 years. Maybe not ideal, but with just an oil change it certainly wouldn't be expected to blow up after a month of driving.
Now, compared to an auto engine, isn't a 320 a lumpy, heavy duty, understressed, low power, low rpm, and low internal tolerance engine?
Is it the oil composition?
Also, of course, the consequences of failure don't exactly compare.

[rigpiggy]

normally its corrosion on the valve lifters, and journals


like this

[cgzro]

Yup, the steel faces of the lifter that take the hard pounding from the camshaft will get a light surface rust coat on them because the cam is up high and the oil drips off it. Then that takes away the hardened coating and the lifters start to wear abnormally fast. Its a very well known lycoming problem. Newer lycomings have roller lifters and are presumably less prone to this problem.

So the engine will not show any problems immediately and with an overhauled fuel pump and fuel system/mags will likely run fine for a while. Then it will rain little flakes of metal from the lifter faces onto the piston skirts and that will scratch the piston walls. That will lead to more blow by, reduced compression, fouled lower plugs, dirty than normal oil. Eventually the flakes will become bigger and the damage to the cylinder walls will be sufficient that the oil in the cylinders will foul the top and bottom plugs. Thats when its usually spotted because you can't clear the fouling with aggressive leaning.

Recently I had my engine overhauled for the second time and when I did I upgraded to roller lifters to try to avoid this problem in the future.

[DanWEC]

That's a great explanation, thanks.

[Badfarmer]

Back to lurking, came across this post;

At the very least (and required by CAR 625 App B Part I item 4(m) Internal corrosion - inspect engines which have not been inhibited and have been out of service in excess of 12 months.)
Best I have found to accomplish this is to remove 1 cylinder per bay and inspect the cam, lifters crank and rod. the worst ive ever seen is a brown furry pushrod. Sadly you wont be able to view the accessory case internals, but the cam and lifters along with pushrods and valve mechanism will give you a pretty good idea. Best to accomplish PRIOR to doing any ground run (as the oil may wash away corrosion or cause irreparable wear). Best to make that part of the purchase agreement and have a personal look inside before you accept the aircraft. Remember you and your loved ones will be inside a few thousand feet up IF the engine quits.

[whistlerboy02]

Exactly what CGRZO says, Its will run fine for 40 hours then start making metal due to a rusted and pitted cam shaft

[DHC2eater]

A few years back I came across a pa12 that a very well known broker/sales/float manufacturer had for sale........same situation as you've found.......they were certain the 0-320 engine was good......we made a deal on condition they remove a cylinder and inspect for corrosion.....

They called back and reported that the engine showed corrosion on the cam/lifters etc......they replaced the cam and other affected parts to make it right.....

Your engine in all likely hood will be corroded internally......

Best Regards

Eater

[Strega]

What you can do,, ** before you start it!!**

Pull the spark plugs, and pull the valve covers, and all rocker arms, spin the engine over with the starter (it spins real easy with the plugs out) until you have oil pressure, and keep doing so for a min or so (the starter hardly gets warm with the plugs out).

Do this a few times, and you will lube up the cam and followers... put it all back together, and this will give the best chance for the lifters and cam to survive..

That being said.. you have a risk with an engine that has not run, and not been inhibited properly...

[PilotDAR]

You've had good advice about the engine, with which I agree. Basically, I would deduct all but a couple of thousand dollars of the engine value from the purchase price. Buy it expecting to zero the engine sooner rather than later. If it goes longer, lucky you! Lycomings do not like to sit. I have an O-320 sitting in my shop right now, but I have done pretty well what Strega has suggested, and that was on a 7 hr since top engine. And my shop is heated and very dry.

But also consider that lonely airframe. I would examine it very closely for corrosion. In the present era of limited parts for legacy Pipers, for me, any corrosion in the airframe would be a no. It you see some, there will be more you're not seeing. Your opportunity in the future to repair that will be alarmingly limited. Legacy Pipers have poor factory parts support, and legacy Cessnas are heading that way. At least though, Cessna defines "negligible damage" so some things can be let go as is.

I'm a fan of older planes, but approach with caution, and a very good inspection! If in doubt, don't!

[ahramin]

If the aircraft is exactly what you want minus the engine situation, purchase it but have $25 000 of the purchase price put in escrow against any maintenance events in the next 2 years or 200 hours.

Check out savvy aviation's prebuy service. They'll basically guarantee you'll catch any problems with a minimum of fuss.