I have a force 120 that runs perfect at 4000 rpm and below. 4000 rpm pushes 18'welcraft cc 27 knts. over 4000 rpm engine loses fire a cylinder and i limp back to the dock. both times this has happened,after i get home to troubleshoot i can find nothing wrong. all 4 cylinders fire and boat runs perfect again. replaced switchbox,same problem.
I am a pretty fair mechanic,i build harleys and drag cars along with boat work, mine as well as others. this intermittent problem is making me crazy because i can not catch it in the act when it drops out. its really hard to check fire in rough chop in the bay.
what are the chances the high speed stator has a bad coil or possibly the trigger or CDI?
it seems that heat may be what is causing the failure because after a couple hours it runs perfect again until 4000 rpm is exceeded for a couple min.
I have a clymer manual but it is mostly about every other motor force makes. shows at least 6 different ignition systems.
I am probably being rash but the clymer manual is as usless as an automotive haynes manual.
I hope i have explained it clear enough that someone would have an idea of what is going on. i am thinking the high speed stator is failing.
i am going to read the manual cover to cover and look for a testing procedure for the stators, pull the flywheel and inspect magnets, and ohm the trigger wires. not sure how to check the cdi.
any help is welcomed
I am a pretty fair mechanic,i build harleys and drag cars along with boat work, mine as well as others. this intermittent problem is making me crazy because i can not catch it in the act when it drops out. its really hard to check fire in rough chop in the bay.
what are the chances the high speed stator has a bad coil or possibly the trigger or CDI?
it seems that heat may be what is causing the failure because after a couple hours it runs perfect again until 4000 rpm is exceeded for a couple min.
I have a clymer manual but it is mostly about every other motor force makes. shows at least 6 different ignition systems.
I am probably being rash but the clymer manual is as usless as an automotive haynes manual.
I hope i have explained it clear enough that someone would have an idea of what is going on. i am thinking the high speed stator is failing.
i am going to read the manual cover to cover and look for a testing procedure for the stators, pull the flywheel and inspect magnets, and ohm the trigger wires. not sure how to check the cdi.
any help is welcomed