1977 4hp Rude, general coil question

[restornator]

got used coils today bought on ebay, they were said to have come off a perfectly running 15hp. I test the spark, 1st cylinder, no spark, 2nd cylinder, excellent spark. Interestingly on the second cylinder, with no spark plug, a spark jumped a 3 inch gap to the rewind starter.

Now before i blame the guy i bought them from, any other way to test it without removing the ends from the connector? i do not have the tool to install the pins into the connector. Also, with one spark, can i assume the power pack, trigger coil, and sensor are good?

 

[psteurer]

Re: 1977 4hp Rude, general coil question

Did you try reversing the coils and then testing again? If the problem stays in the same cylinder then you know the problem is in your motor. If the problem shifts to the new cylinder, then it is likely a bad coil that you got. It sounds like a bad coil based upon the last sentence in your first paragraph.

 

[F_R]

Re: 1977 4hp Rude, general coil question

Did you try reversing the coils and then testing again? If the problem stays in the same cylinder then you know the problem is in your motor. If the problem shifts to the new cylinder, then it is likely a bad coil that you got. It sounds like a bad coil based upon the last sentence in your first paragraph.

No kidding? It actually jumped a 3 inch gap? I knew they were strong, but not that strong.

Anyhoo, to answer your question, no you cannot assume the power pack is good just because you have spark on one cylinder. They have separate components within the pack. But the other stuff should be good. I agree, swap the coils.

BTW. cranking it over without having the wires attached to a spark gap is pretty rough on the coils and should be avoided. Perhaps you destroyed an otherwise good coil???

 

[restornator]

Re: 1977 4hp Rude, general coil question

No kidding? It actually jumped a 3 inch gap? I knew they were strong, but not that strong.

Anyhoo, to answer your question, no you cannot assume the power pack is good just because you have spark on one cylinder. They have separate components within the pack. But the other stuff should be good. I agree, swap the coils.

BTW. cranking it over without having the wires attached to a spark gap is pretty rough on the coils and should be avoided. Perhaps you destroyed an otherwise good coil???

I think my one question, is how do i swap the coils without f'ing up the female connector? i don't have the tool to remove the pins. Can i use a lead tester to bypass the connector?

No, the dead one never fired. That large spark jump was after i tested that one, i didn't reinsert the spark plug.

 

[AlTn]

Re: 1977 4hp Rude, general coil question

I used a small rod to force that female connector out far enough to capture it with a pair of needle nosed pliers and pull it the remainder of the way out. I lubed it with WD 40 first. To reinsert, just push it back in a little at a time with the needle nosed. With the coils attached to the PP, you should have at least 150V, DVA measured, on each orange wire from the PP to coil. CDI has a great test procedure for this. I recently went through a no spark on one coil, with a '78 9.9 evinrude. PP and coil both were bad. As a first time poster I'd like to thank the many who helped me with the 9.9 and a '76, 6hp, fisherman I'm currently working on. A raw novice, of which I'm one, can learn from your experience and knowledge which you so willingly share.