The inlet valve on my qualcast classic is not sealing so I lose compression and the engine will not start. I have delved quite deeply without completely stipping the engine - How do I adjust the valve clearance.
Thanks

Phil., July 2009

after lapping in the valves to adjust clearance you have to file the valve stem spindle end's
if the mower has been laid up the valves can stick open remove the valve cover plate and watch movement of both valves

wirecutterman, July 2009

well you need to know if your valve seat and valve is clean. and im talking about has it got pitted hoels in the valve seat and valve. if it does you need too use some valve compound to reseat it. and sometimes it will take taking the valve out to reface it.and allso ck your clearance between the valve and your tappet it could be wrong. dont know what engine you have so i dont know ok.

Dennis, July 2009