1976 johnson 35 running on 1 cylinder

My 1976 35 hp johnson is running really rough, and it runs on 1 cylinder and once in awile the second kicks in and runs ok. When it does kick in, it runs at full speed fine, until I slow down, and then it coughs and spits and eventually shuts down. Any help would be appreciated.

Re: 1976 johnson 35 running on 1 cylinder

Sounds like a coil may be failing. When it happens pull one plug wire at a time to isolate which cylinder is not firing.

Re: 1976 johnson 35 running on 1 cylinder

I have this engine and it had the same problem you might have.

Under the flywheel is the armature plate that is part of the magneto system and the bearing supporting this plate will wear and cause the points not to operate properly and the ignition will misfire. This plate will not move around much at WOT as it is locked against the timing stop and the engine sings like the great engine it is. You can check the excessive movement by supporting the plate between the fingers of each hand ( ENGINE OFF and in neutral ) and see if it will move allot side to side. If you have this condition, then search for Joe Reeves solution found on this site.

I did Joe?s procedure and adjusted the coils to the recommended position but they still hit, so I moved them back to where a fingernail would catch on the mounting boss.

Make sure you torque the flywheel nut to 105ft. lbs. or you will have new set of problems.