This misfiring is driving me crazy!! Can anyone help?

[bostonwhalermontauk1965]

Hi guys


I thought I had this one figured out - but no such luck. I have had what seems to be a dead upper cylinder. I have made improvements to the way the motor is running , but it still stalls out when pulling off the bottom plug wire when running. It is a 1982 Johnson 50. It seems to have had this problem since I got it running again recently, so here are the steps I took to try to correct it. I first took a compression check - 135 lbs in both cylinders. After that checked out, I rebuilt the carbs being it was never done previously, and I even installed new floats. I put in new wires and plugs, and it has awesome blue spark at both cylinders. Everytime I do something different to improve this, it makes a difference for the better, but it still has a miss and I am at wits end. Can anyone suggest something else to look for? It has gas, spark and compression, so what the hell else is it lacking? I never messed with timing or anything. I know the upper cylinder is getting gas because both plugs come out with a rich looking condition. Thank you - Paul

 

[Will Bark]

Re: This misfiring is driving me crazy!! Can anyone help?

Check yor flywheel key and make sure the flywheel is torqued down correctly. Good luck.

 

[Lyle29464]

Re: This misfiring is driving me crazy!! Can anyone help?

I would try switching things, Carbs, plugs and then look deeper. Reeds.

 

[bostonwhalermontauk1965]

Re: This misfiring is driving me crazy!! Can anyone help?

I just checked - flywheel was tourqud down fine and the key was in the right location for Top Dead Center. Now I am really stumped. What are the symptoms of a bad stator, or of a bad CDI box. Can a faulty CDI box produce spark but be at the wrong timing? What the heck else am I missing here? I really dont get it.

 

[Daviet]

Re: This misfiring is driving me crazy!! Can anyone help?

A couple of quick checks you can do to isolate your problem. Use a timing light and check spark on both plug wires with the engine running. Use a squirt bottle with fuel mixture in it and squirt fuel directly into the carb with the engine running. Hopefully this will tell you weather you have a fuel or ignition problem.