Hand lapping valves?

I am re-building an old Hercules OOC motor from a 1937 Cletrac. I'm sure the valves are similar to any old flat head motor. An old Harley rider who happend by looked the machine over and said I should be able use the old valves and hand lap them in after cleaning.(This was also mentioned by a new friend.)I've never done a valve job and Im arfaid Im a little clueless. I've seen the tool...(THINK I get it?)... and understand the concept of using lapping compound to "grind in" the valves. (Hope the valves aernt too pitted after removal and cleaning.) Any pointers,tricks, or a walk thru would be greatly appreciated.

Two pistons sat out of the motor for nearly 10 years and the tractor sat for nearly 40 years before that. The pistons have cleaned up very well except for some baked on oil/carbon inside the pistons and ring grooves. (I think this stuff is an immature diamond). I've tried soaking in parts cleaner (even hot) and penetrant oils and nothing seems to soften it up. I did manage to scrape and scrub the grooves clean and chip away most of the rock hard "stuff" baked onto the inside of the piston...But Im hoping theres a better way. I've considered a weak muratic acid but Im afraid of harming the brass insert or pitting the cylender...are my fears well founded? Any other suggestions?

Highest Regards,

Steve

If the seats are in bad condtion you will need them to grind the seats as well. Then lapping will not be needed.

Try soaking the pistons in hot water. Believe me, it will disolve. It might take a day, but it WILL disolve the carbon.

I use a break a piston ring and use the sharp end to clean ring grooves. Takes some elbow grease, but works well. The old ring is also the right width to clean the groove. Doc.