I've got a 78 ski-doo everest 444 L/C and it's going through spark plugs like crazy. I throw in a spark plug and I'm lucky if I can get a days use out of it before it craps out. Does not matter what brand plug I use, I've tried bosch and ngk. What happens is the plug will start to mis-fire then eventually it will crap out all together. Visually, the plug looks fine when I take it out, just wet, but when I test for spark, it won't spark at all. Put a new plug in and I'm good to go, for a while anyway. Always seems to do it on the cylinder on the clutch side of the engine. I can't figure it out. The plug on the recoil side is always fine. I've done new wires and plugs, cleaned the carb, the plug cap on the side that always dies out tests out to around 1420 ohms, the other cap tests out to around 1580 ohms. I don't really know what else to look for. I did a compression test on it once it was warmed up a lil, both cylinders checked out to 120-125psi. I just can't figure it out!? Why is the plug on the one side just not lasting? I'm going to check point gap and timing but I don't really think that's the problem cause it runs so good once I throw a new plug in.