i have a 1994 formula z 583 rave that has a plug fouling on the mag side only. it has been to two dealers the following has been done.floats ajusted &needels check&set,carbs cleaned,compression check 130lbs both cyd.,primer check ok,pressure tested for oil seal leak ok,scoped in cyd ok,new wires&caps,hotter plugs,exhaust check ok.after all this it is still fouling out the dealer seems to think it could be the rings .please help with any other ideas????????????