Van's Air Force
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Don't want to see this ...
- Thread starter DanH
- Start date
Yeah, but this sort of damage happened before it got parked
I am not sure about oil but grease maybe. Can it use grease as a way of lubricant
Gotta wonder if that Tappet face had been ground by a shade-tree “overhauler” and then not re-hardened….
Many years ago I worked for a helicopter operator/ maintainer and we overhauled mostly HIO-360-D1A engines that produced 190 hp and turned 3200 RPM. They had a 1000 hr overhaul, and few made it.. Lycoming hadn’t figured out the cam issues and we had cases of failed cams and lifters that had nearly every lobe wiped out and all tappets looking that bad or worse. It didn’t help that the engine was started with no load, and they would overspeed to 3400 RPM or more pretty easily which would damage the cams. Full flow filters saved the bearings from metal contamination.
An (automotive type) compression test would have detected this failure as it was happening.
Not enough known history. Removed from a Mooney a long time ago, probably because the screen was full of metal. Probably sat on a tire in a dusty corner for 20 years, while those with firsthand knowledge died or retired. Then barn-find fantasy entered the picture, and it became a valuable discovery...Look Bob, here's a nice Lycoming no one noticed...
It's likely, although not my call. Bad one is original 1970's vintage.
No overhaul in the log.
I should add a postscript here. At pre-buy, I had already stuck a scope in the cylinders and noted obvious piston pin cap scuffing and a lot of bore wear. So, the current owner bought this engine knowing it would need to come apart, the only question being how far. I think we'll be seeing more of this decision, given the run up in new engine prices with very long wait periods. Bought right, a fellow can spend money and come out well. When complete, this owner will have a like new IO-360...and know what he is flying behind.
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Bill Boyd
Well Known Member
My O-320 did that within 100 hours of such an "overhaul" by an A&P very well known in the experimental community, more for his legendary aircraft design work than for his engine rebuild business. He came to realize through my experience that it was not acceptable to "polish" pristine-looking cam lobes and tappet faces with crocus cloth and reinstall tappets in random positions vs. the holes they came out of. He rebuilt my engine properly a second time on his dime and it has run fine since for over a thousand hours at last report. We all learned something that day. Failure showed up at oil change - "is that used oil coming out, or silver roof paint?!" No notable effect by then on engine performance...
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Sam Buchanan
been here awhile
Yep, I've seen this movie. I purchased an O-320 E2D from a well-known salvager for my new 1999 RV-6 (used engines in new RVs were common in those days) and after 140 hrs compressions started getting soft and saw some flakes in the oil screen. The engine was still running pretty well, even transported me to Arizona and back. But after pulling a cylinder hoping for just a top overhaul the kiss of death was discovered.
Fortunately the remainder of the bottom end was rebuildable and it got four new 160hp Millennium cylinders. The engine has served me faithfully since 2000. I suspect the corrosion occurred or accelerated while the engine was in storage following hurricane damage in Florida.
N804RV
Well Known Member
Guy across from me has a 182 that he says he flys once or twice a month, and often less than an hour. He says his oil temp and pressure always seem to be on the low side. He is now waiting on a factory reman IO470 because his cam is badly pitted and a couple of his lifters look like the ones in the picture above.
My suspicion is that he just didn't fly often enough or for long enough to burn off all the crap in his oil. I've been told several times that once this wear pattern starts, cam lobes can deteriorate very quickly and lead to catastrophic failure within just a few hours.
My suspicion is that he just didn't fly often enough or for long enough to burn off all the crap in his oil. I've been told several times that once this wear pattern starts, cam lobes can deteriorate very quickly and lead to catastrophic failure within just a few hours.
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BoydBirchler
Well Known Member
I have 2 cams that look just like that one. First failure was with the first run engine at 1900 hours on my Mooney 201, second failure was 740 hour SMOH and 2 years later (new came and lifters a MOH not a re-grind) Airplane flew 250 to 350 hours a year with regular oil changes and oil analysis. Oil analysis gave no warning of failure.
RV7 To Go
Well Known Member
I also have a cam and tappets like the ones in the picture. Freshly rebuilt O-360 from a supposedly reputable rebuilder. First oil change at 10 hrs showed a little metal in the filter. Told it was normal for a fresh rebuild. Second change after another 25 hrs showed a lot of metal in the filter. The new nitrided cylinders were able to be honed. New pistons, bearings, cam and lifters, oil pump, oil cooler...many $ later running again. Still good after another 700 hrs. There was no noticeable performance difference while the cam was disintegrating. The lifters had been reground but apparently were not rehardened.
