Johnson 70 vro issues

[Andy456]

hi guys my brothers having some issues with his outboard runs fine compression all good will run for 30min or longer with no issues but then when go past 3k it misfires and the overheat alarm goes off. If he starts and goes full throttle has no issues seems to only misfire once it’s warmed up. Replaced all the coils and cleaned the carbs but still the same. It’s running on premix too now.
Any input would be great

 

[jakedaawg]

Well, if the overheat alarm goes off it's probably getting hot. Service impeller and thermostat.

model number will get you better answers, some of those had a service bulletin way back when...

 

[racerone]

Posting the model # should be required before allowing a post.