72 Johnson 100HP will not start

[racerone]

Re: 72 Johnson 100HP will not start

The purpose of the safety switch is to prevent the engine from CRANKING over when throttle is advanced too far.----Does not prevent it from sparking at the plugs.

 

[Daviet]

Re: 72 Johnson 100HP will not start

The saftey switch supplies the ground for the starter solenoid. If you ground the white wire on the switch to the block, and the starter now works, the switch is defective or out of adjustment.
Maybe this will help you out.
http://www.maxrules.com/graphics/omc/wiring/100-125_1971-72.jpg

 

[57 7.5]

Re: 72 Johnson 100HP will not start

Thanks, I've ordered a new safety switch. Now should the button on the switch be all the way out or in for it to start? It was all the way out and I've pushed it all the way in and still didn't allow it to turnover. Just wanted to see if it was just not adjusted right. Thanks, I never tried to let it start when it was grounded cause I wasn't sure if it would hurt it or not. So i'll see if it will start now that I know how it works.

 

[Daviet]

Re: 72 Johnson 100HP will not start

I beleave the switch has to be all the way in to pass voltage, use an ohm meter to check it out to be sure.

 

[57 7.5]

Re: 72 Johnson 100HP will not start

Roger that, will do. Well it wouldn't fire so I pulled the two plugs (one at a time) on the right side and neither have spark, got too late so I'll check the other side and start trouble shooting the no spark. Thanks to everyone who responded the help was welcomed and you guys are the best. My next post may be 72 Johnson 100 hp no spark! LOL