1972 Evinrude 65HP bogging on WOT

[Deadonthewater]

I have a 1972 65hp evinrude that will not open all the way up on WOT. I have taken the carbs apart and cleaned them, but this has not helped. I plan to order a set of carb kits and rebuild the carbs. Does anyone know if there is a common problem with these engines that could be causing this? I have had it out twice this summer without much luck. It has opened up and planed out a couple of times, but the last time out it wouldn't go above half speed. Any suggestions? Could it be ignition? Is there some test that anyone could recommend. Any help would be appreciated.

 

[Daviet]

Re: 1972 Evinrude 65HP bogging on WOT

If it were me, I would start with a compression test. Make sure the spark will jump a 7/16" air gap. Over haul the carbs paying attention to the high speed orifices, make sure to remove the core plugs on top of the carbs and clean the tiny passages underneath it.