2005 Johnson 90 hp problems-help

[nottelybill]

first the bulb will not pump up tightly. at the same time mthis happens the motor got a vibration about every 30 sec. that would last about 5 msec. and the rpm level would drop about 300 then return to normal. any ideas? what about service bulletins?

 

[racerone]

Model # is ?

 

[nottelybill]

J90GLSOB it has Carbs

 

[racerone]

Primer bulb should firm up when carburetors are full and float valves close.--------------Find out by looking into carburetor throats to see if one is overflowing.--------You could hook up a timing light ( as a scope ) and see if there is an ignition miss.---------Put it on each cylinder and observe the flashing when RPM drops.

 

[nottelybill]

I tried to pump till gas ran out of one of the carbs but never did after many many pumps. I will try that but don't think that but got a feeling it show up. Thanks