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I have a 50 hp Johnson outboard that won't run. down to no spark from plugs and the plugs are new. I think it is the ignition coil. Could anything else keep motor from getting spark from plugs?
You need to check spark with a spark tester set at 7/16". If you don't have one you can get them t any auto parts store.If you are losing spark on only one cylinder, chances are it is the coil but it could be the power pack as well. The easiest way to test for a bad coil is to swap the small wires from one coil to another. Crank the engine and see if the loss of spark stays on the same cylinder. If it does the ignition coil is bad. If the problem moves with the swapped wire then the power pack is probably bad. Do these tests and let me know what you find and we can go from there if necessary.
Is there a way to check the power pack?
Yes, no spark on that either. Yes, I have an ohm meter.
Here we go:
brown to brown yellow 826
Orange to orange/black 416
white to blue 27
white to green 28
As for disconnecting the black/yellow wire and recheck still no spark. That is if that wire is in the same connector as the brown and brown yellow wires. Only black/yellow wire we could find.
The only other tests we can do you will need a peak reading voltmeter. In the absence of that tool, the only conclusion we can make is that the power pack is bad. By taking the black/yellow out of the circuit it rules out the stop switch and key switch and harness. Both your timer base and stator are about right. The stator is a bit high but not unexpected with a different temperature. So by process of elimination we have to conclude the power pack. I would recommend changing it for a new one. Thanks
So I need to keep watch on the stator.
Thanks so much for all your help. I feel better about changing power pack out now.
Just to let you know I have spark now. It still doesn’t start but one step at a time.
Fuel was my next step. I just want to let you know how it went.
The primer system close under the flywheel I notice drip fuel little. That’s not enough to cause air leak is it to keep from starting?
Maybe that’s why plugs get so wet then while trying to start it. I guess it is to replace or take apart and replace internally parts then. Not check test for it is there?
After getting spark and trying to start it would basically back fire.
If it is backfiring, check the flywheel key that it isn't sheared. You can check the timing with a timing light. To test the primer carefully pull off one of the small lines, squeeze the primer bulb, if fuel comes out it is leaking.