90 hp Yamaha spark arc problem?

[bajarosa]

Have a late 80's 90 Yami that runs good at idle and WOT. When i bring the throttle back down to a low rpm, it runs crappy for a moment and dies. I start it back up again and seems to run fine. I gave it a Seafoam treatment and it seems to run better except for the same problem. One thing i noticed when i had the cowl off, i got a shock when one of the wires arced as i was reaching over it. Could a bad wire or coil be my problem? What else can i check to troubleshoot? Any ideas?

 

[david_r]

Re: 90 hp Yamaha spark arc problem?

welcome to iboats!!!

yes a bad wire or coil could be the problem.

do you have a good blue spark with a good snap?

the best way to find a bad plug wire without shocking yourself is to start the eng in the dark with the hood off.

i would lean more towards a loose wire in the remote control box since it only does it when you power down.... a bad coil or plug wire would most likely effect power at a more consistent rate.