Cost of overhaul

I think it depends on what they find when they strip it. (And on whether you’re intending to keep, or sell – to someone who doesn’t get the logs scrutinized by an expert. )

A pity you didn’t mention what engine you are talking about. Some manufacturers try to limit options – Rotax seem to have a bad reputation, refusing to sell replacement cranks, for example – but one can always inquire.

But as already pointed out, it seems logical no quote can be given before the engine has been opened. Or if you get one, it will be very high, to be on the safe side.

Seeing your location, above all do talk to Loma Air!

They are fixed in a quote, but only part of the accessories are included and any big times that were not inspected at time of quote would be on top. A good example would be a bad cam – hard to know before you open engine up.

I can’t recall exactly what was included in my IO-540 overhaul, but it was the manifold, injection system, I think starter and generator, but that was about it. In general, make sure you have about twice as much money as the quote – that’s what it’s going to be in the end when all is said and done.

On the old types e.g. Lycomings, the overhaul price is, as Adam says, fixed in the quote, but the quotes vary quite a lot between companies.

And to a large degree you get what you pay for, with the good firms doing a generally good job and maybe doing some extras, while at the other end of the spectrum you get one particular company in central Europe which changes the cylinders and paints the crankcase and calls it an “overhaul” and of course their quote is pretty low

You also have the option of sending the engine to the USA where the value for money tends to be better (as well as a lot more companies with a good reputation than in Europe) but there are other hassles; see e.g. here.

airways wrote:

So there is no such thing as a “manufacturer’s definition” of what an overhaul is ? A certain set of parameters every shop needs to uphold? I’m thinking of a continental engine

Here is Continental’s service bulletin that describes replacement parts for anything that will be documented as an overhaul in the engine’s logbook. It is three pages but in most maintenance regimes it is mandatory by government regulation. That leads us to the basic principle that what you (with your A&P mechanic) do during engine overhaul is between you and government, the company that made the engine originally is only of interest to the extent that they have published approved data on the subject. Today the OEM doesn’t even have a lock on supplying parts, aircraft engine parts are made by competing independent companies that have government (PMA) approval and you can overhaul an engine using relatively few parts from the OEM.

The basic regulatory definition of overhaul is that the engine is disassembled, measured and inspected, then reassembled with all parts within service limits, and also in compliance with manufacturer overhaul data like the three page SB linked above. Otherwise, there is no requirement to do anything to any engine part that is still within service limits. An overhaul is not by regulatory definition a process by which an engine is returned to new condition, although obviously many engine owners try to achieve that end as long as you ignore potential fatigue issues with anything that is reused, e.g. the crankcases and crankshaft. Other owners do not, and in many cases that is very useful to them. For instance if a part is very slightly out of new specification at first overhaul, after 2000 or more hours, accumulated experience may indicate that it’ll still be well within service limits after 4000 or more hours, in other words for another overhaul cycle. Engines like a Continental can be overhauled several times, so the larger job is to manage the engine over say 8000 hrs of service life, not just 2000 hrs.

Peter wrote:

And to a large degree you get what you pay for, with the good firms doing a generally good job and maybe doing some extras, while at the other end of the spectrum you get one particular company in central Europe which changes the cylinders and paints the crankcase and calls it an “overhaul” and of course their quote is pretty low

Interestingly, when we asked half a dozen firms in Europe for quotes for an engine overhaul, only half bothered to answer and of those that did the lowest quote was from the firm which several times here on EuroGA has been called the “only reputable” firm in the UK for engine overhaul! We got a quote from a well-known central European company (I don’t know if it the same one that you were referring to) which was not only substantially higher but also would replace fewer parts with new ones.

Silvaire is right but I would never accept an overhaul unless the whole engine was built to NEW limits.

It’s not exactly difficult to achieve. Maybe a few more parts to be changed an I doubt the extra cost would reach 4 figures (of course it depends on the engine history; if the previous five overhauls were also to service limits…). The two rebuilds I have had (SB569 crank swap in 2008, and the exchange engine a year ago) were both to new limits. Both were done by the same company BPA and I got lucky on this scandal because BPA used a load of Superior PMA parts instead of the Lycoming ones. However BPA cannot give you an EASA-1 form, and while this is not an obvious connection I do wonder just how many companies who can would be using Superior PMA parts… there is an ethos in Euro-land that you should use only the “proper parts”.

only half bothered to answer

That’s a very high success rate for GA