No spark on one plug

[DallasJeff]

Working on a '67 Evinrude 33HP

Got it running at idle but no power at WOT. Cleaned the carb, new carb kit and float.

Checked compression: 115-120 psi on both cylinders.

Spark plugs are Champion J8C and one is sparking strong (blue arc and shocked the hell out me ) but the other is dead. I moved the working plug to the other boot and still no spark so its not the plug. What next?

 

[Camo Joe]

Re: No spark on one plug

May be the points and or condenser.........but look for any shorts or breaks in the wiring pertaining to that cylinder.............If the motor has set a good while the points may be corroded.............It could also be the coil gone bad........

 

[Vic.S]

Re: No spark on one plug

Spark plugs are Champion J8C

Recommended plugs are J4C, gapped at 0.030".
J6C may be Ok if you need a hotter plug .... but J8C ???.... could just be too hot .... but not the cause of your problem.

as suggested; coil, points or condenser.

 

[samo_ott]

Re: No spark on one plug

Very high chance it's a coil gone. You will have to pull the flywheel and check underneath. Could be points also, but they're easy to clean. Chances are you have original coils which are toast. They fail with age.

 

[DallasJeff]

Re: No spark on one plug

Will change the plugs to J4C and look for a flywheel/harmonic balance puller while I'm out.

Are coils for this motor ('67 Rude 33HP) a common part that can be found at boat dealer/repair shop or will I have to mail order?

Meanwhile I'll check and clean the points.

 

[samo_ott]

Re: No spark on one plug

The coils are a dime a dozen. About $20 each. They used em for years and years in many models... You can order them right here from iBoats.