Lycoming 0360 camshaft

[jerholz]

Hello all,
I'm an A&P (not for a living though) helping out with a Mooney that hasn't run since 2009. We were concerned about the camshaft rusting from sitting for so long, so we pulled a cylinder to have a look. We didn't find any obvious rust, but it didn't look like I expected. Would someone who tears down engines regularly take a look at these pictures and let me know if this is typical?

The cam lobes and tappet faces are smooth to the touch, but, as you can see, there is a lot of discoloration on the cam. Maybe baked on oil and/or coating worn off? I suspect the reddish areas are worn and the other discoloration is some kind of deposit.

If it matters, it's an 0360 A1D, 180 hp, parallel valve engine with about 1000 hours (and probably 30 years) since overhaul.

What do you recommend for cleaning off the deposits?

Thanks in advance.

Jerry

[vaflier]

The reddish areas appear to be rust to me. Cam is headed south. Choices are fix it now or run it as long as will make full power while checking oil sqmples for metal.

[martymayes]

??? Who did the last engine overhaul? And when? What does the follower look like?

[skyfixer8]

I would run / fly it locally for maybe 10 hours, take sample and check for metal. Apparently the engine wasn t prepared for long term storage properly if done at all.

Bill l

[Mike Switzer]

I would run / fly it locally for maybe 10 hours, take sample and check for metal. Apparently the engine wasn t prepared for long term storage properly if done at all.

Bill l

Then after the 10 hour sample change the oil & sample again after another 10 hours.

[cub builder]

What you are looking for is pitting on the face of the cam followers. If the cam follower is pitted, it will trash the lobe. If the cam followers have no pitting, the cam lobes are unlikely to spaul. While it does happen, I have yet to see a cam lobe fail without a matching cam follower with a rust pitted face.


Most pitted cam followers aren't this bad, but it is an example of what you are looking for.

-Cub Builder

[Tom Downey]

The pictures in the first post are perfectly normal for 1000 hours.

The black stuff is parkerizing, picture is a new cam.