1978 85hp help..!!

deac1234

Seaman
Joined
Apr 25, 2010
Messages
67
Ok brief history:

Motor has been getting harder to that start, Then, when you get it started it sounds like it was running on three cylinders. Did the spark gap test and got confusing results. Top cylinder starboard side had no spark. reversed coil wires and had NO spark on top OR bottom (?). Put wires back and had spark on both (?). Next morning back to original problem. no spark, top cylinder. Went and bought top coil, still no spark. Reversed power pack and problem went to the other side of the motor. Put them back and still no spark top cylinder. Bought new power pack and all 4 cylinders had spark. Let it set a week (weather sucked) and tried it again today all good. Took boat to lake...hard start and when it did start wouldn't idle. Let it warm-up and starboard side doesn't get warm. Took boat home and no spark starboard side top or bottom, then suddenly it had spark again. REcheck all connectors etc..nothing corroded or loose. Pulled plugs, starboard side wet with gas...

observations: Compression 120lbs all four cylinders.
Even when working, spark on starboard sides seems
intermittent.

(Sorry no inductive timing light..( wish I had one!)

What might cause this. Timing base? Stator? Rectifier?

Questions:

How to check all of the above?

What should a mechanic charge to check this out IF I have to go that way?

How hard is it to change stuff under the flywheel?

Thanks,

Kerry
 

Daviet

Fleet Admiral
Joined
Sep 24, 2008
Messages
8,958
Re: 1978 85hp help..!!

An OEM manual will ansewer all those questions and many more. It's a wise investment and guide you through the troubleshooting.
 

deac1234

Seaman
Joined
Apr 25, 2010
Messages
67
Re: 1978 85hp help..!!

Rapidly running out of time (it is Sept in Michigan after all..) and money..

Question. I replaced the upper coil...then the power pack.. now I'm doubting myself and wondering if I switched the coil wires (top for bottom) by mistake when inserting them back into the connector. Is there a way to check to see if I have it right..? (only TWO wires, leave it to me to accidentally mix them up....!!)
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: 1978 85hp help..!!

Each powerpack should have two orange wires, one of which will have a blue tracer. The blue goes on top of that cylinder bank or cylinders one and two.
 

deac1234

Seaman
Joined
Apr 25, 2010
Messages
67
Re: 1978 85hp help..!! (the story goes on and on and..)

Re: 1978 85hp help..!! (the story goes on and on and..)

Thank you sir!, Turns out I had it right....


Bought an inductive timing light. Good light all 4 cylinders Hmm took boat back to lake... started right up...idled fine. de-trailered, out to the lake.. boat ran like a scared cat.....

I was going to haul it down to the mechanic and have HIM check it out too. Now right back at square one. Not much point in taking a running motor there I guess.. especially at $95.00 per hour!

Oh and...came back to the dock to take boat out..looked over at trailer and it seemed to be tilting. A closer look revealed a broken leaf spring!

It never rains but what it pours...

Kerry
 
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