Home › Forum › Ask A Member › 1976 Johnson 35HP magneto problem › Re: 1976 Johnson 35HP magneto problem
Was wondering how your ignition worked out after replacing the plugs and boots?
I had this same problem with the spark arcing on the outside of the plug on my 1976 9.9. Same scenario, all new ignition ,perfect timing. I cleaned the boot interior and the exterior of the plug well and retested. Was ok for awhile then started arcing along the outside again. I noticed that the trouble plug had its boot installed farther onto the plug compared to the other spark plug that was behaving itself. After cleaning the plug again I reinstalled the boot out a bit from its original position and it cured the problem. In addition to not using dielectric grease which would have helped,i think it was the terminal was closer to ground than the spark plug terminal,the spring terminal was installed a bit past the spark plug terminal itself ,and the spark would rather go the path of least resistance and distance than rather jump the gap.
"Some people want to know how a watch works, others just want to know what time it is"
Robbie Robertson