Help with lapping valves near KMMV

[mill2978]

I’m looking for help to lap valves in two cylinders of a Lycoming O-290G that’s been converted to a D. The plane is located at KMMV.

There will be at least two people to help including the builder/owner.

The engine has low compressions, oil consumption is up, however it’s putting out near full power at flight RPMs.

It’s likely an exhaust on one cylinder and the intake on the other based on the sounds it makes and what can be seen with a bore scope.

Please PM me if you or someone you know in the area is experienced lapping valves on this or similar engines.

Thanks

 

[jrs14855]

If its a 0 290D2 it has mechanical lifters with adjustable rocker arms. Check for proper clearance. D2B has hydraulic lifters.