Noisy lifter or stuck valve in Lycoming 8 in line?

[John Gelfer]

After warming up, my 1928 Gardner with the 225 cu. in. Lycoming 8 (GT series motor) is making some top end noise that sounds like a stuck lifter. It runs fine, and you only hear it when it idles, but you really notice it when you shut the motor down. When you turn off the ignition, you hear 3 bell like "tap,tap,taps". It sounds like it's from the front of the valve train. I just checked all valve clearances, and only cylinder #3 needed adjustment.

Assuming I can isolate which valve is causing the noise, what's the easiest way to fix it?

[GLong]

If it's a sticky valve, remove the spark plugs, use a light and a bent piece of wire to follow the valves, rotate the engine slowly, with a crank or socket on the front crank nut/bolt.. when each valve is open use your favorite oil/penetrant to soak the valve stem of the open valve, do this for all valves. Rotate the engine some more,, then run it again.

I'm not sure from your description that it's in the valve train. But just keep eliminating possible noise-making possibilities and eventually you will find the noise..

GLong

[Rusty_OToole]

Did you adjust the valves? Try adding Marvel Mystery Oil or similar product to the oil and/or gas and going for a long drive.

[Friartuck]

Consider runnig one or two pints of Seafoam cleaner in the crankcase and fuel system.

http://seafoamsales.com/sea-foam-motor-treatment/

Wouldn't suggest it if it didn't free up lifters and valve train.

[DavidAU]

Sounds like a stuck valve.

Warm the engine up and then with it running at a fair speed pour some MMO down the carby ( you will probably smoke the neighbours out but it will kill the midges).

Add a pint in the gas tank and take it for a long ride.