Johnson 100hp running problems

Firebirds

Recruit
Joined
May 30, 2012
Messages
5
Hey all,

Sorry in advance if I have missed a thread on this issue with the answer.

I have a 1972 Johnson 100hp that has driven me up a tree in the last few months as I have attempted to get it and the boat (68 StarCraft cuddy cabin) back into sailing shape, after sitting for about 8 years.

​​​​I could get the engine to turn over but not fire up, so after doing some trouble shooting replaced the coil and pulse pack and removed the cutter circuit. Now she runs! BUT only when the key is held in the start position.... 🤬

The starter will kick down and the engine will run while the starter is getting power when I keep the key in the start position, but as soon as I release it to the on position it quits.

Ive gone through the cdi trouble shooting guide and all my voltage's check out, so now I'm kinda stumped. Something I noticed is after the pulsepack was replaced my choke seems to only intermittently work. Before it would move into position with the key in the on position and go full when the toggle was pressed. Now it just seems to move a tad and every now and then will kick fully into position.


Am I right to assume my next step is to replace my keyswitch? Looking at some wiring diagrams I noticed the overheat horn is also in the the circuit and was wondering if it could be causing some problems. Or a wire needs to be jumpered or moved because of clipper circuit removal?


Any help would be great, I'd hate to have to pay someone to fix this, especially if it's simple. Just haven't had much experience with pulsepacks and outboards.


Thanks!
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,610
Sounds like it might be as simple as installing a new ignition switch.----Perhaps it has the wrong switch in it now.
 

Firebirds

Recruit
Joined
May 30, 2012
Messages
5
I'll be putting in a new switch hopefully over the next few days, gonna be 116+ tomorrow so might have to wait on that. I'll let y'all know once it's done.
 
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