90hp merc. electical issues

[i try]

1987 3 cyl.#ob196221..have spent last 2 days sifting thru post,this is a great resourse,maybe you can help me a bit farther.motor ran fine..suddenly started surging at top speed,thought maybe something got sucked thru carbs as it ran fine again,then again with the surge and die also, hard to start back up. compresson is at 120 for all 3 -spark alternates on bottom 2 cyl.sometimes there sometimes not. rectifier test shows no continuity anywhere. is the rectifier the source of my problem?is that good comp.for that motor?if my ignition switch got stuck[weak return spring]could this cause damage?thank you very much

 

[Laddies]

Re: 90hp merc. electical issues

First a bad rectifier can cause those type problems, disconnect it and test run the engine to see if that stoped the miss. A stuck ign. switch should not cause a problem but a faulty ign. switch that is backfeeding voltage to the ign. system can destroy the system, so if disconnecting the rectifier don't help disconnect the black/yellow wie from the box and test run the engine. Remember with the black/yellow disconnected the engine won't turn off with the key.

 

[i try]

Re: 90hp merc. electical issues

thanks for the quick response,when i disconnect the rectifier,do i just tape off the wires that go to it-or connect them to each other as they were on post on rectifier?

 

[Laddies]

Re: 90hp merc. electical issues

Tape them seperately and they should be on seperate terminals on the rectifier not both on 1 terminal.

 

[i try]

Re: 90hp merc. electical issues

thank you ,it is a rainy day in georgia i will post back on results..this is a great site

 

[i try]

Re: 90hp merc. electical issues

disconnected rectifier,taped wires to each other as they were on the post,fired right up on muffs in driveway.good spark on all 3.runs much better.many thanks..can i use boat like this until my rectifier comes in from cdi?--not far,just once to the honeyhole[about 1 mile]

 

[Laddies]

Re: 90hp merc. electical issues

Yes but tape the wires seperately not together.

 

[i try]

Re: 90hp merc. electical issues

i have three terminals..the+ has 2 red wires...bottom right has 2 yellow...bottom left has a yellow and a grey..on the test i taped them togather,red-red...yellow-yellow....yellow -grey,seems to run ok..you said tape them seperate ,so i should take these apart and tape off all 6 wires with none going to another?thank you for your patience

 

[i try]

Re: 90hp merc. electical issues

ok ,after more research i am thinking all 6 wires seperately.it may run both ways but seperately will keep my stator from overheating?

 

[i try]

Re: 90hp merc. electical issues

ok ,after more research i am thinking all 6 wires seperately.it may run both ways but seperately will keep my stator from overheating?

is this correct?