Possible cause of blown powerpack?

[troutmaster1972]

Ok thanks in advance for any help Heres the story 1997 Johnson 70 hp motor has had 3 powerpacks blown and replaced by the shop Finally after the last one they replaced, said enough is enough, you are not solving the problem and are totally done with them Decided to try to figure it out myself. Ohm checked the coils and stator as good, the rectifier is running the tach and charging the battery. What I did check almost as an afterthought was the continuity of the spark plug wires Only one of the 3 had continuity My question is would 2 bad spark leads cause the power pack to blow? When it does it actually bubbles the surface of the powerpack. I have my doubts something this simple would cause it but wanted to find out from you all Thanks again for your time

 

[oldcatamount]

Re: Possible cause of blown powerpack?

If you have two bad plug wires out of three, that means the electric charge wasn't being grounded out (by the plugs) so, yes, that scenario would fry the pack and maybe coils to. I learned (the hard way) to ground the spark plug wires when testing an ignition system or it will over load the pack (and coils). I can't explain the technology, but I know it does happen.

 

[troutmaster1972]

Re: Possible cause of blown powerpack?

Thanks for the advice Guess I am lucky that the coils still test out good Just bought new wires and now I wont be so afraid of frying the power pack again when I try it out

 

[clanton]

Re: Possible cause of blown powerpack?

The sparkplug wires should have copper wire core. Charge coil voltage output to pack should be verified for correct voltage. The power pack mounting bracket bolts should be checked, if loose pack looses ground. Check pack wires, they rub the bracket and short to ground.