1985 90hp johnson fuel pump problem?

[schang]

Hey everyone,

The boat is running almost perfect, except another problem.

When I am in gear and going forward, in about 10 seconds the fuel cuts off. I would have to choke the motor to start it again. Starts up fine. In gear and going forward, the problem happens again the fuel would cut off again. My brother would pump the inline hand fuel pump connecting to the motor and the motor will run all day but we would have to pump every ten or so seconds ( we would take turns pumping). My question is could it be the fuel pump not working right and sending fuel into the engine? Or could it be a clogged inline hand fuel pump? Or other problems, any suggestions or ideas will be very helpful. I am thinking about installing a fuel pump over the hand pump to see if it will solve my problem.

Thank You in advance,
S.Chang

[bktheking]

Pretty good chance the fuel pump needs replacing.

[psteurer]

Could definitely be the fuel pump. Do some simple things first: check to make sure you have the vent open on your fuel tank. Remove the big screw on the fuel pump and clean the filter screen.

Are you running okay at idle? If so, you could have a clog in the high speed jet on one of the carburetors.

[Johnsonfan14]

Its definitly your fuel pump.i had that problem with my 115 johnson but once i changed it that was the problem hope this helps.

[jonesg]

Its definitly your fuel pump.i had that problem with my 115 johnson but once i changed it that was the problem hope this helps.

Likely, not definately until the other possible causes are eliminated.
A clogged tank vent will produce the identical symptom.

If you read these pages regular you'll see, more than once, people who were advised to change the pump, $460 later they find out the pump was good , they just had some dirt in the tank vent.

[cougar1985]

Likely, not definately until the other possible causes are eliminated.
A clogged tank vent will produce the identical symptom.

If you read these pages regular you'll see, more than once, people who were advised to change the pump, $460 later they find out the pump was good , they just had some dirt in the tank vent.

ive also run into faulty aftermarket primerbulbs that will give you fits!

[kenmyfam]

Air leak in the lines, bad venting could well be part of it. My guess is most likely the fuel pump failing though.

[emdsapmgr]

Are you running an original type combination oil/fuel pump, or has it been converted to a standard pump where you premix the oil in the fuel?