2003 j90plstc won't stay running at low idel into gear

[adominique0313]

2003 Johnson 90Hp j90plstc 2 stroke (V4)
My engine started something new? The engine will not run correctly at low idle. once warmed up runs kinda okay but when just starting it stalls a lot until I prime the bulb. it gets really bad when I shift into gear it boggs and then stalls only at low speed. once I get it to pass the low speed it runs fine. here are some of the issues that I think are causing the problems 1)the primer bulb between the gas tank (built in 18 gallon tank) will not stay hard ( I replaced the fuel line and bulb between the tank and the fuel filter) 2) the timing sensor does not move smoothly. that is all I can think of I don't think it has anything to do with the carbs although I could be incorrect.
the Johnson dealer in my area said it is the fuel pump with out looking at it and they want 500 dollars
thanks for any help

 

[adominique0313]

bump
nothing
come on any ideas

 

[tblshur]

One would think if it runs good at wot the fuel pump should be good .before spending bucks give these guys a chance to respond they are great may do a decarb good luck. :joyous:

 

[adominique0313]

thank you will wait for more response's

 

[jakedaawg]

When you say the bulb wont stay hard what exactly do you mean? If, without attempting to start the boat, can you squeeze the bulb and make it get hard? If it does get hard does it stay hard while squeezing lightly on the bulb? If either the aforementioned do not happen look for leaks by following the fuel lines inside the cowling. If bulb wont stay hard and no leaks can be seen you may have a heavy float/bad needle or seat, leaking gasket for the VST cover, just so many places.

The idle problems you describe could also come from a dirty throttle body/carb. Or ignition related.

Take a fuel sample, look for cloudy or phase seperated fuel even if you just put fresh gas in. Do a simple open air gap spark check at 7/16". Do a compression test and report back. Someone will help but will also want these answers first.