Nissan 90A running on one cylinder

[gdoss]

This old 90A is now running on only one cylinder. I pulled the plug wires to detect the problem and found only #1 would keep it running. My question is: is there any use in going any farther and spending $ and time or sell it for parts and cut my losses?

 

[Sea Rider]

Re: Nissan 90A running on one cylinder

If in good running shape stay with it, could be ignition coil or CD related issues, if so, check prices and parts availability. If NLA, it's a different story.

Happy Boating

 

[pvanv]

Re: Nissan 90A running on one cylinder

Also check compression. You want all cylinders equal. 5% difference means a minor issue... 10% means rebuild time. After 20 years, you could have almost anything causing the problem. Verify carbs are well cleaned.

 

[gdoss]

Re: Nissan 90A running on one cylinder

Checked compression. All cylinders within 5 lbs of each other. Pulled plugs and they need changing pretty bad. Hooked up plugs to see if there was any fire. They all showed good sparks to the eye. Could the coil be weak or what should i look for next. Back when it was running, it would run good for a few minutes and then drop back to 4000 rpm. Never figured it out. Haven't used it in last six months.

 

[TOHATSU GURU]

Re: Nissan 90A running on one cylinder

One or more of the trigger coils or a CD or anything else. You can either randomly change out the parts or start the ignition troubleshooting procedure.