1976 Johnson 70 running weird

[Mach1Boater]

I have a 1976 Johnson 70hp motor that will run great for awhile on the water I will shut it down for a little while to fish then I will start it up (starts easy) but wont rev over 2000 rpms for about 10 min then will run at 5500 rpms till i shup it off again. the motor has the 3 carbs rebuilt, new coils(all three) new advancement plate, new power pack, and new plugs. to me it sounds like its flooding when i shut it off but im not sure...

 

[Daviet]

Re: 1976 Johnson 70 running weird

A couple of checks you might try when it woun't rev up.
Check spark to each plug, you can use an inductive timing light an you don't have to pull any plug wires.
Remove the air box on front of the carbs, use a squirt bottle with fuel in it and squirt fuel directly into the carbs and see if it picks up.
These checks might help you determine if it is a fuel or spark problem.