Johnson 20R73 A firing problems.

[Rohan2]

I have a 73 20hp Johnson which was gave to me. Very clean motor. Throttle, shift linkage and tilt all work smooth. The kill button is gone. So the wires coming from the magneto, split from the coils to the kill switch are unplugged(since the kill switch is not there to plug in). I am getting no spark at the plugs. I took the hand crank and flywheel off to inspect the points and magneto. They look brand new, are in great condition. Gapped at .02. Everything looked new or very clean under the flywheel. How can I troubleshoot to see what is not letting my plugs spark? Is there a way i can check for spark before the coils? Even when there is no kill button? Also, all wires ohmed out.
Eager to get this 20 running..
Thanks

 

[boobie]

Re: Johnson 20R73 A firing problems.

The place to start is to get an OEM factory service manual if you want to do this work yourself.

 

[ultra353]

Re: Johnson 20R73 A firing problems.

It will still spark with no kill switch, its there to "kill the spark". Double check the points for oxidation, sometimes they look clean but have that layer on them. Get some 400-600 wet type sandpaper and run it through the points a few times. Then use electrical contact cleaner or acetone to clean any residue left behind.

 

[kbait]

Re: Johnson 20R73 A firing problems.

If the 2 wires that are unplugged from the kill switch touch each other, they'll ground the points and no spark. Those wires cannot be touching each other for spark to occur. Good luck!