No spark on #3 - '73 85HP Evinrude

[RaoulR]

Not much hair left... heh!

The engine overheated so the waterpump impeller has been replaced. The guy who did the werk said the the stator had melted so I replaced it. Still no spark on #3. Replaced the Powerpack and then the #3 coil, still no spark. I switched the powerpack connectors for the 2 starboard coils and the problem moved to the other coil, meaning no output from the #3 coil connection on the powerpack to the coil. Where do I go from here?

I have the original Evinrude service and parts manuals for this engine. It talks about using a special neon tester for checking the charge coils, etc. but finding one of those will be impossible.

How can I figure out what's wrong? I have both an analog and digital multimeter at my disposal. I've been canibalizing a '74 115 for the powerpack and coil.

 

[RaoulR]

Re: No spark on #3 - '73 85HP Evinrude

Anybody got an idea, please?

 

[darrklim2]

Re: No spark on #3 - '73 85HP Evinrude

Not much hair left... heh!

Replaced the Powerpack and then the #3 coil, still no spark. I switched the powerpack connectors for the 2 starboard coils and the problem moved to the other coil, meaning no output from the #3 coil connection on the powerpack to the coil.

If the problem moved to the other coil I would say that you need a new power pack??? But that would be kind of odd since you say you just replaced the powerpack. Did you replace it with a new powerpack or a used donor powerpack???

 

[darrklim2]

Re: No spark on #3 - '73 85HP Evinrude

Replaced the Powerpack and then the #3 coil, still no spark.

Did you try to start it after replacing the powerpack before replacing the coil? Maybe the old coil was shorted out and in turn wrecked the new powerpack on the same connection??? It's a long shot but is a possibility.

 

[RaoulR]

Re: No spark on #3 - '73 85HP Evinrude

Yes, I ran it before I put the donor coil on.

... and I thought about the donor powerpack being bad, but on the same plug? It's possible I guess but the guy whose motor I got it from said the motor ran fine when he parked it. Maybe I'll just take the whole motor next time, LOL!

But seriously, I'm really perplexed by this. From what I've been reading, it would be easier to diagnose if I was missing spark on pairs of cylinders instead of just one. I'm gonna pull the flywheel again and do a continuity check on all the wires.

 

[RaoulR]

Re: No spark on #3 - '73 85HP Evinrude

Did you try to start it after replacing the powerpack before replacing the coil? Maybe the old coil was shorted out and in turn wrecked the new powerpack on the same connection??? It's a long shot but is a possibility.

I've thought about that too. Would a shorted coil blow that circuit?

 

[RaoulR]

Re: No spark on #3 - '73 85HP Evinrude

OK, I put the original powerpack back on and now all 4 coils have spark... So I guess I diagnosed a bad coil and the powerpack I 'borrowed' has a bad #3 coil output?

I dunno, it makes my head spin... all I know is that it werx! Just had it out on the lake and all is well!

Thanx for the friendly advice all. It's nice to come to a new forum and not get at least one flame job!