4000 RPM Max sometimes on 90HP Johnson year 2000

zenwriter

Seaman Apprentice
Joined
Nov 1, 2010
Messages
41
Running at 5,000 RPMs the engine hesitated and then maxed out at 4000 RPMs: top end of throttle had no effect. At dock the plugs looked OK and no water in the separator.

Next time out had the same issue, but then it started to stall and run rough at lower RPMs.

Headed back to dock in 5 MPH zone, then tried WOT again. Started to bog and then shot up to normal operation and is running fine now, top RPM in the 5500 range.

Mechanic says it's probably an optical ignition issue: He doesn't test and replace individual components, wants to install new coils & an ignition repair kit ($700-plus).

Any thoughts as to the problem ? My idea if to keep running it and see what happens (I have Sea Tow).
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Keep that part changer mechanic away from it and run it until it quits. Then you'll know what's wrong with it.
 
Top