rebmo
Seaman
- Joined
- Jul 2, 2007
- Messages
- 60
Re: 72 Johnson 50 No spark DOA!
OK, after lots of trouble shooting and help from members here I found the culprit. The safety switch that does not let the motor start mounted on the side of the motor that detects if the throttle position is in neutral failed. This switch in my case was gunk ed up and the spring was shot. It was stuck in a near on/off position. When I went to jump the solenoid with a remote starter switch it let out a little plume of smoke. I removed the white wire that runs from the solenoid to the safety switch and ran it to ground and the motor started and produced spark all day long today. I removed the switch and found the contact to be stuck and opened it up and found scorch marks where the internal contact was barely being made. The spring was fatigued and had no ability to fully push the contact back out when the cutout in the throttle plate was in front of it representing neutral. I have a new switch on order and can operate the motor now with the switch wire to ground (but not too safe as it could start with the throttle advance in gear).
Thanks to everyone, especially FillupD for all the help troubleshooting this gremlin. If you have one of these motors you might want to check this switch and if you do get stuck you can just remove the connector and touch it to ground to test or work around.
Steve Lund 14' Johnson 50hp 1972 Anniv Ed
OK, after lots of trouble shooting and help from members here I found the culprit. The safety switch that does not let the motor start mounted on the side of the motor that detects if the throttle position is in neutral failed. This switch in my case was gunk ed up and the spring was shot. It was stuck in a near on/off position. When I went to jump the solenoid with a remote starter switch it let out a little plume of smoke. I removed the white wire that runs from the solenoid to the safety switch and ran it to ground and the motor started and produced spark all day long today. I removed the switch and found the contact to be stuck and opened it up and found scorch marks where the internal contact was barely being made. The spring was fatigued and had no ability to fully push the contact back out when the cutout in the throttle plate was in front of it representing neutral. I have a new switch on order and can operate the motor now with the switch wire to ground (but not too safe as it could start with the throttle advance in gear).
Thanks to everyone, especially FillupD for all the help troubleshooting this gremlin. If you have one of these motors you might want to check this switch and if you do get stuck you can just remove the connector and touch it to ground to test or work around.
Steve Lund 14' Johnson 50hp 1972 Anniv Ed