Help with spark on a 1970 Johnson 85 H.P

[wildman59]

I have a 1970 Johnson 85 H.P (model number 85ESL70D) Hydro electric shift. I am getting no spark on any cylinder. I have checked and cleaned the points which didn't help, I had a bad wire going from the power pack/Amplifier to the points under the flywheel i repaired, and I still have no spark. The power pack/Amplifier looks to be in new condition so i know it has been replaced somewhat recently so i am not sure what i should look at next. Is there a way to check the power pack? Is there a kill wire or something i could check? Does anyone know where i could find a diagram online for the wiring of power pack or power head so i can check that the wires are hooked up right for the power pack and power head? Or any other advise on what to check next would be greatly apprciated. Thank you.

 

[wildman59]

Re: Help with spark on a 1970 Johnson 85 H.P

Ok, ive tried some trouble shooting and heres what i have come up with so far. I took a light tester and when the key is on i have power on the purple wire that goes from the power pack to the main wire panel on the motor. I also checked the main coil wire which goes from the coil to up under flywheel and i have good spark on that main coil wire going from coil to the distributor under the fly wheel, but I have no spark on any of the 4 plug wires. Is there a way i can check the power pack with my light tester to see if it is whats burnt out? like i said earlier it looks to be new but if theres a way i can check it to know for sure that would help. Also if theres any other wires i could check to try to pin point this it would help. Does anyone know where the kill wire is so maybe i could check that? Thanks again.

 

[Daviet]

Re: Help with spark on a 1970 Johnson 85 H.P

If you have spark going to the dist cap and no spark coming out, I would suspect the rotor is shorting to ground.

 

[wildman59]

Re: Help with spark on a 1970 Johnson 85 H.P

So if i have spark going from coil to the distributor cap under the flywheel does this mean i can suspect the power pack is good? If your guessing the rotor is shorting out how can i trouble shoot that? Thanks again.

 

[wildman59]

Re: Help with spark on a 1970 Johnson 85 H.P

Thanks for all the help. I found the problem. What was happening was there was alot of corrosion built up on the distributor cab so when the rotor was going around it was sending any power to the plug wires because there was so much corrsion build up electric current was able to get through to the plug wires. One last question, i also had replaced part of the wire that runs from the power pack to the points and the new wire i used to replace the part that was bad is a little bigger than the wire on the power pack is this a problem? Do i need to have the exact gauge wire to keep it from burning out my power pack? Just trying to keep myself from burning out a power pack.