Help with '76 70hp evinrude

[orangewarner]

Bought boat & did not expect motor to run but compression was good and it does run. Linc&syncd ran motor 1 hour ran great. Then stopped boat, tried to start from a stop and boat would not get onto plane it would run good up to the point of planing then reduce in RPMs checked carbs they are clean, replaced fuel lines& pump. found #2 ignition coil only sparking 1/4" across tester. It needs replaced clearly but does this symptom sound typical or should I be considering other test. motor was idling good, no unburnt fuel in exhaust, but have noticed now a slick on the water still idles smooth even idles with 1 splug removed.

 

[xtraham]

Re: Help with '76 70hp evinrude

very common problem with the 3 Cly's it more than likely needs the carbs rebuilt, and they have to be extremely clean by removing core plugs, soaking, a good rinse then blown out with compressed air, and new kits installed

 

[xtraham]

Re: Help with '76 70hp evinrude

oh and before you replace the coil make sure all connections are good and clean and check the grounds, you can swap the coils and see if the week spark follows that coil