1991 88hp SPL - fuel bulb won't stay firm, loses pressure

[bobwirg]

I have an Evinrude V4 non-VRO, that I've had for 10+ yrs. Runs great except last week I startedhaving problems with fuel pressure.

if I run it even for short periods the fuel pressure goes away, and when I try to throttle up again it boggs and stalls. re=pump fuel bulb and it will fire up and run fine. tanks are vented and it still happens.

This happens with two different tanks and two different fuel lines so I believe the problem is beyond the external fuel lines within the engine. I ran it witht the cover off at idel and did not see any obvious fuel leaks.

I am curious to know if this could be an internal leak in the fuel pump, or what else could cause this problem.

Thanks for any help that you may have on this.

Bob

 

[Will Bark]

Re: 1991 88hp SPL - fuel bulb won't stay firm, loses pressure

By having to pump the fuel bulb to stay running that ponts to a failing fuel pump or an air leak somewhere before the fuel pump.

 

[bobwirg]

Re: 1991 88hp SPL - fuel bulb won't stay firm, loses pressure

By having to pump the fuel bulb to stay running that ponts to a failing fuel pump or an air leak somewhere before the fuel pump.

Thats what I expect as well. I did not see a fuel leak so I am planning to replace lines before buying a new pump.

Is there and easy way to test a fuel pump?

Bob

 

[Will Bark]

Re: 1991 88hp SPL - fuel bulb won't stay firm, loses pressure

Disconnect the fuel line at the carbs and put end in a jar; crank the engine and fuel should come out in strong steady spurts. Good luck

 

[Silvertip]

Re: 1991 88hp SPL - fuel bulb won't stay firm, loses pressure

Primer bulbs do not stay firm when the engine is running. Fuel is "sucked" through the line so there is no pressure in the line.

 

[bobwirg]

Re: 1991 88hp SPL - fuel bulb won't stay firm, loses pressure

Purchased a pump erbuild kit. plan to rebuild tomorrow, also replaced primary fuel line between pump and connector in lower engine shroud.

 

[bobwirg]

Re: 1991 88hp SPL - fuel bulb won't stay firm, loses pressure

OK just to close this out. I took the fuel pump apart tonight and found that both internal check valves had holes in them. Did the rebuild tonight. i expect that this will completely correct the issue.