Buy with low-hour engine, or high-hours and replace / overhaul

[SDB73]

Hi All,

I'm just looking at buying a cheap, fun, first aircraft in which to complete my PPL, and get a few hours under my belt before moving up to something a bit bigger and faster.

I'm conisdering a Warrior, or similar, and want to avoid as many minefields as practical.

I'm considering two options :
1) Buy one with relatively low engine hours to give me (potentially) reduced chance of engine niggle, or more importantly, engine failure!

2) Buy one with very few hours left on the clock, and so at a greatly reduced price, and get a Lycoming factory overhaul, or similar, so I end up with a basically "new" engine.

I favour the second option, as at least then I'll know the history of the engine.

Any opinions / experience?

Any good advice as to the most painless / reliable way to go about effectively zero timing the engine?

[Pilot DAR]

Depending upon the regulatory opportunities where you fly, I recommend that you but run out, and keep it running as long a you can, while building up your own engine reserve. Perhaps your authority allows "on condition" engine maintenance. You may find that even a run out engine will happily operate well past "factory" TBO. It may only need "something" fixed in that interval, not "everything" yet.

I bought my C 150 with 1700 since overhaul (plus, I suspect a few hundred more), and ran it to 3150 hours before I overhauled it (factory TBO 1800 hour). When I finally did overhaul it, I found that the metal which I had discovered in the oil filter, which triggered the decision, was only from a tin cap on the alternator drive coupling, and did not at all justify the overhaul. Nothing else in the engine jusified the overhaul, but I was already into it anyway. The engine would have run on for quite some time yet.

The other aspect is that after you get comfy with the plane, and build a good relationship with the maintainer, you might be able to help with the engine "re and re" when the time comes, which both saves you money, and helps you learn. If you buy a plane with a fresh engine, all of the choices have been made for you, and you're paying top dolllar for someone else's work - like it or not. Add to this, they might have chosen to not do something else while the engine was out, which you might have chosen to do, now that opportunity is lose to you for a while.

Budget carefully, but airplane ownership is a wonderful experience...

[IO540]

I would press the seller of the plane with the runout engine down to the lowest possible price and then get the engine overhauled by a reputable shop in the USA e.g. this one (http://www.bpaengines.com/) which did mine in 2008.

Then you know what you are flying behind, rather than having some mismanaged rusted up old heap in front :)

[Big Pistons Forever]

Before answering your question you have to decide if this is a step up aircraft or are you planning to keep the aircraft for a long period of time. In the latter case than getting an aircraft with a run out engine is a better deal because you will start with a known quantity.

One thing that is often forgotten is engines have both hour and calendar manufacturer limits (eg for a C 172 lycoming engines it is 2000 hours and 12 years). This is a big issue for privately owned aircraft as most engines on these aircraft are not used enough. Again Lycoming recommends that it is necessary to fly the aircraft at least once a week in order to obtain full engine life. Failure to regularly fly the engine will inevitably result in internal engine corrosion and shortened engine life. It is important to note that just running the engine on the ground is not good enough you need to fly for at least 20 min to bring the engine up to full operating temperature and boil off the acids in the oil and the moisture inside the engine. Almost no private aircraft get this frequent use and so an aircraft with a low time engine can often be a poor bargin. For example a fellow at my home airfield paid top dollar for a C 172 with a 300 hr old Lycoming engine that was factory remanufactured (ie zero timed by the factory, the best and most expensive overhaul). Unfortunately no one paid attention that the overhaul was over 10 years ago and the aircraft log books showed long periods where the aircraft did not fly. At the first oil change there was a lot of metal in the oil and the engine ended up needing a new camshaft, lifters, and 2 cylinders were too badly corrosion pitted to reuse. The total repair bill was in excess of $12,000:ouch:.

The only way to know the condition of an engine with certainty is to have one cylinder removed so that the camshaft, lifters, and general internal condition of the engine can be directly examined.

The airframe also suffers from standing. The airflow generated from flight will help ventilate the aircraft structure removing moisture and condensation. Aircraft structures can develop sever corrosion damage from sitting, especially outside, but even inside, unless the hanger is heated and ventilated.

With respect to high time engines, as pilot DAR said, many engines can be safely operated well past TBO , but these are invariably in aircraft that see regular use. The school I teach at part time regularly runs their C 172's to 2600 hours with no problem. For this reason if you are looking at a C150/152/172 or PA 28 aircraft ex flight school machines can be very good deals. It is easy to determine the reputation of the school, so you can avoid operators who do not take reasonable care of he aircraft, high time is actually good as it depresses the price, but the likely hood that you will have many years of trouble free flying at a typical PPL level of utilization left is high.

[IO540]

One needs to see the logs to get an idea of how often it has flown.

If it has seen periods of a few months without flying, the engine can be considered gone (unless there is clear evidence of it having been preserved) and you need to discount the price accordingly.

However one cannot be sure about anything - logbooks can be easily forged - unless you can get some independent corroboration of the seller's story.

Professional opinion (from somebody working for you) is a must, anyway. This may be a few hundred quid.

Beware scams where the seller is charging for a viewing. There is a TB20 for sale whose apparent seller is asking for a 10% deposit just to view the plane, but there is some question mark over whether the seller is the owner... if you get my drift ;)

[Maoraigh1]

An engineer working for you, preferably the guy who will maintain it if you buy, is essential, even if it means paying him to travel a long distance. But look at the aircraft yourself first. Get to understand log books before going to look at it. If your engineer thinks it worthwhile, pay him to inspect it.
The last time our group bought a plane, we looked at several where it didn't need an engineer to reject them. (e.g. logbook with a mandatory AD missed - owners engineer insisted it had been done weeks before, but nothing entered in the logbook. If he had said they'd missed it we might have accepted it)

[A and C]

At the moment I have an aircraft in the shed for an annual check.
This aircraft had just been perchased by the owner, the half life engine is scrap, a number of the AD's clearly had not been done, some of the flex hoses were falling apart the cowls had perrished mounts and the baffels had fretted holes in them.................and that is just the start.

Clearly the aircraft had seen next to no maintenance in the last few years resulting in rusty bearings and the like.

If I had been sent to inspect the aircraft I would have walked away before flying it as it was clearly a dog. The guy is now about to pick up a bill for twice what the aircraft is worth just to get it back to an airworthy state. Please dont make the same mistake I geuss he was of the opinion that the cost of an engineers time was expensive, well maybe but it is very cheap if you avoid an aircraft like this!

Make sure the the inspector knows the aircraft, the devil is in the detail with AD's for instance there is an AD on the PA28 main gear leg that if it has been done all the way to the terminating action will save you up to £6K over the next few years of ownership.

[AdamFrisch]

Many in the know agree that a run out that's been maintained well and most importantly flown regularly (you want to see at least 100hrs/year) is a good buy. Many aircraft make it well past TBO, so just because the engine is closing in on it doesn't mean you don't have many years of flying still ahead of you.

Mike Busch, aka The Savvy Aviator, talks a lot about this in his columns at AvWeb: The Savvy Aviator (http://www.avweb.com/news/savvyaviator/)

Repair, don't replace. Overhaul only when it's come to the very end of the line.

I have myself just bought an aircraft with engines that only have 300hrs left on them, so hopefully this will stay true for me as well.

[A and C]

Good luck Adam !