My friend has a 93 yahama pro v 150 with a new power head that fouls out all the plugs every other trip to the lake. Thanks for any info on this problem.
Just a guess, engine running to cold, wrong sparkplug, float/float valve in carb, propped wrong, weak ignition system. New powerhead may just need link and sync.
Not sure which models, but some Yamaha's use 2 different ignition systems on a same model size. The plugs are totaly dedicated for each system, and will not interchange. Be absolutely sure you have the right plugs to start with!!!
