Small Engines (Lawn Mowers, etc.): Sticking intake valve, coleman pressure washer, 0000 steel wool

Question
Hi Eric,
Thank you for your assistance.  I have a Techumse Enduro OHV
5 hp 4 stroke engine on a Coleman pressure washer.  The engine has run fine for several years (maybe 30 hours).  The last time I used it the intake vlave stuck open and the engine quit.  After a little investigation, I removed the head and plastic hammered the valve out.  It had brown deposits on the stem and the guide looked ok?  I used a very light emery cloth to remove the brown deposits from the valve stem and reassembled it.  The valve moved freely in the guide.  I adjusted the valves and started the engine -- it ran fine for about 15 minutes then the valve stuck again.  Any suggestions on how to make the fix last longer than 15 minutes would be appreciated.
Thanks,  Jim  

Answer
You may have to replace the valve guide.  I would try cleaning the guide before replacing it. Remove the head, remove the valve and then use some #0000 steel wool to clean the inside of the guide.
Wrap some steel wool around a drill bit smaller than valve stem so it fits inside the valve guide.  Use a drill to turn the bit.  The steel wool on the outside of the bit will polish the guide.
I would also run some Sea Foam or Marvel Mystery oil through the tank to clean out any old residue.
Let me know if this helps.
Eric