That is QUITE the stretch Tom... Looks more like corrosion issues then actual wear problems.....
...I am out... When one wrestled with a pig, all one gets is dirty...
Spalled cam and lifter pictures..
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That is QUITE the stretch Tom... Looks more like corrosion issues then actual wear problems.....
...I am out... When one wrestled with a pig, all one gets is dirty...
tyndall
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I'll see what I can find tomorrow. They look like what Tom posted except with a groove cut through the lobes.
Tom-D
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That is QUITE the stretch Tom... Looks more like corrosion issues then actual wear problems.....
I am out... When one wrestled with a pig, all one gets is dirty...
Cam and lifer problems always start with some thing.
And you can always bail when you have been proven wrong by making some wise azz remark.
Yes, poor manufacturing and quality control to add to the parts counter bottom line where the big profit margins lie. It is not an inherent issue.
Tom-D
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No Henning it is a design flaw, The TCM engines do not have these problems. Lycoming designed the cam to lifter junction to lie flat to each other, and the lifter is flat on the bottom so the lifter sets square with the cam and makes contact to 100% across the cam lobe. They hoped that the lifter would hydroplane on the oil film and prevent wear.
It didn't work.
TCM on the other hand, sets the lifter to cam junction so as only one half of the lifter rides on the cam lobe and has a domed bottom. As the cam turns the lifter will rotate as it is driven upward distributing the wear over a greater area than the lycoming.
Want to see it proven? pull a valve cover on a TCM engine and watch the push rod rotate.
Lycomings won't
Stewartb
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Don't TCM lifters actually contact the cam while Lycoming has the followers? Not that it probably makes much difference. TCM cams have failed, too. Not as many as Lycoming, but Lycoming has better cylinder compression history so I guess they're even. These engines are designed to be flown more often than the average modern owner flies them. That's the root of the problem in my view. Problems with low time engines like the OP's aren't all that common. It would be good to know the history of his cam and followers, too. I'm not ready to throw Lycoming under the bus. There's are a lot of healthy engines out there.
Tom-D
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Failure is a problem with all machines.
TCM lifters have a body that touches the cam, with a hydraulic unit within the body that actually is part of the lifter assembly
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petrolero
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Here are some pics of cam spalling and cylinder corrosion found with a bore scope (down the oil filler) during my pre-buy in 2012. The engine is a Lycoming O-540 and this engine's history included a lengthy idle spell in coastal Oregon.
http://www.pilotsofamerica.com/forum/showpost.php?p=1550243&postcount=153
http://www.pilotsofamerica.com/forum/showpost.php?p=1550243&postcount=153