I was watching the “Flying Reporter” on You Tube about how the engine in his group shared plane (which he likes to give the impression is his own Aircraft in past videos) was condemned at the Annual.
I am really interested in your opinions here. Initially he speaks about the engine being low in compression and points out valve seating problems and also shows the valves concerned. So it would seem that valves merely needed regrinding to seat them properly. Then suddenly, as the engineers can’t get proper compression as presumably they have not sorted out the valve seating, they suddenly start pulling off cylinders (really invasive maintenance which often causes MIF).
Note that the most up to date Lycoming instructions are if you can’t get proper compression, then re-seat the valves, run the engine and then Borescope. If you still can’t get proper compression Lycoming now admit the compression test is highly unreliable and basically just believe the Borescope.
I can’t see that a worn camshaft could cause valve seating problems. In a Lycoming you can’t see the cam so I would have thought that a worn camshaft could only be detected by (a) metal in the oil filter or (b) low power from the engine due to low lifting valves not allowing the engine to run efficiently.
It seems to me that the subsequent discovery of a worn camshaft was purely incidental to the main problem. I know there is a Lycoming test where you check pits in a camshaft with a sharp pick and see if it catches to determine how bad the cam wear is. The video shows something going on with the camshaft. I am interested in opinions. I would have not allowed my engineers to start pulling cylinders off for a valve seating problem. I presume there really is a problem with that cam but there was no mention of the engine making metal…………….see video below.
I don’t really understand the engineering side of it, but I found it fairly ridiculous that a group of 6 seem bowled over by the fact that their 2200 hour engine needs and overhaul, and they have less than half the money required to do so. Furthermore they’re talking about scrapping the aircraft! I guess an OH for that is going to be in the region of £20000 and if they have half in reserve then it’s going to be little over £1500 to get it back for a fresh 2000 hours. Surely a no brainer for all involved.
Would one be right in observing that the hangar owner (the name briefly appears) has been reported as having a condition of the hangarage contract that they also do all your maintenance?
I agree with Zuutroy. And the airframe doesn’t appear to be in a knackered condition. Also I am not convinced that this wear
is anything unusual. Maybe an engine specialist can comment?
I had understood that the aircraft is based at Redhill and maintained at Biggin Hill so it would be in the hangar of their chosen engineers rather than the hangar owner imposing the engineers on the group.
It looks very much like that cam is scrap ( but the photo is not great ). The engine has run 200 hours past TBO and yet there seems to be surprise that an engine running “ on condition “ has finally given up.
The group should have arranged their finances to replace the engine at 2000 hours and taken the extra 200 hours of “ on condition “ flying as a bonus to bolster the groups finances for unforeseen events.
The engine has run 200 hours past TBO
I didn’t catch that. In that case they damn well should have the full OH amount (20k+) in their bank!
Surely if we are talking about the “bottom end” – ie crank/ cam etc. a non turbo Lycoming, if regularly used with regular oil changes should be able to do 3,000 hours easily.
It is in a group so probably regularly used, but we don’t know if it has ever stood around, hence possible rust/pitting on the cam lobes. I still don’t like the non logical way the issue (if it is an issue) was discovered.
I don’t like to bang on but my 80hp Rotax 912 is 200 hours short of 5000 hours and it’s done that on nothing but consumables. Although I do include carb rubbers in that.
Bit silly not to have a sufficient engine fund. Which personally I would like to have banked well before 2000 hours.
It is a YouTube video, so expect some drama on engine servicing 
200h past TBO is a good record, I don’t think any wear should come as surprise? or probably have been picked in oil analysis in annuals before?
On financials, I don’t know how come aircraft shares keeps their value without an 30k£ engine fund, say 15£/h (an aircraft without an engine is worthless as far as the pilot view/use is concerned, having a 10k£ engine fund will not add anything to it)
Bathman
I seem to remember when CSE aviation ran the commercial flight training at Oxford the maintenance program on the Lycomings was to run the bottom end to 4000 hours with top ends replaced at 1000 hours all on straight oil, the UK military do quite well with most of the Lycomings they run making TBO so the conclusion is the Lycoming is a reliable engine as long as it is regularly used.
It is a pity that no one has entered the market with a 180 HP Rotax style engine and you have to ask why ?
