Birdman84
Seaman Apprentice
- Joined
- Sep 14, 2015
- Messages
- 42
I have been trying to trace down a low RPM miss on my 2 stroke Johnson 90 and still unable to figure out the cause. It misses at idle speed up to about 1600 RPM's then smooths out. It occasionally will die out in put into gear at idle speed. Here is what I have done so far in the past 3 months:
Replaced optical sensor, coil packs and power pack - all new OEM (had a no spark problem)
Carbs rebuilt by mechanic
Replaced spark plugs, plug wires, water/fuel separator, fuel filter
Checked fuel pump diaphragm, unable to see any signs of fuel delivery problems
Replaced key switch assembly - OEM (another no spark issue)
Replaced stator - used OEM (mine looked pretty bad. The used one I bought appeared to be in good condition)
Right before replacing the stator it started giving me misfiring at all speeds, so this issue has progressively gotten worse as time has gone on and I continue to run it. After replacing the stator it is now back to just a low RPM miss but I am concerned that whatever the problem is, may be causing damage to the stator or other electrical components. It seems odd to me that I have had recent issues with so many electrical ignition components.
I have performed DVA and resistance checks on the ignition components but all readings have been good (this is in a barrel at home). If I pull one of the 2 plugs on the right (looking from behind the motor) the RPM's do not change. If I pull one of the two on the left side, the motor sputters and almost dies out.
Any suggestive advice on what to check next would be greatly appreciative.
Replaced optical sensor, coil packs and power pack - all new OEM (had a no spark problem)
Carbs rebuilt by mechanic
Replaced spark plugs, plug wires, water/fuel separator, fuel filter
Checked fuel pump diaphragm, unable to see any signs of fuel delivery problems
Replaced key switch assembly - OEM (another no spark issue)
Replaced stator - used OEM (mine looked pretty bad. The used one I bought appeared to be in good condition)
Right before replacing the stator it started giving me misfiring at all speeds, so this issue has progressively gotten worse as time has gone on and I continue to run it. After replacing the stator it is now back to just a low RPM miss but I am concerned that whatever the problem is, may be causing damage to the stator or other electrical components. It seems odd to me that I have had recent issues with so many electrical ignition components.
I have performed DVA and resistance checks on the ignition components but all readings have been good (this is in a barrel at home). If I pull one of the 2 plugs on the right (looking from behind the motor) the RPM's do not change. If I pull one of the two on the left side, the motor sputters and almost dies out.
Any suggestive advice on what to check next would be greatly appreciative.