|
Danny -- Tough question to answer. Why is the valve sticking? If it's simply a "gummed up" stem -- oxidized oil between the stem and valve guide -- you may well be able to free it with some chemistry. Berryman B-12 Chemtool is one of the best crud-cutters on the market, and applying B-12 to the stem-to-guide junctions, preferrably at both the top and bottom of the guide, with some mechanical push-pulling may do the trick. Some people dump a pint of B-12 in the crankcase and idle the engine for ten minutes. If you do this, drain the oil while hot and replace the filter (if so equipped). Other solvents, including commercial "crankcase flush" of various brands, Liquid Wrench, Rislone, and Marvel Mystery Oil, can be used in the same way but will usually take longer to work. The Rislone and Marvel Mystery Oil can be used as oil additives, and I'd personally be inclined to use a stronger solvent in the old oil, drain, and then add the Rislone or MMO to the fresh oil. It's also possible that the valve is sticking because it's mechanically blocked -- perhaps a piece of junk got into the engine somehow -- or because the valve stem is bent. If the cause is mechanical, it's wrench time because chemistry won't take the junk out or straighten the valve stem. Good luck with it. John
| 
