Stalling on trottle up

[rpruski]

I have a 1996 Crownline 5.7LX Merc Bravo One Engine Serial #OF795033 boat will Idle and run at full throttle anything in between it dies out. I changed out the MAP, IAC, Throttle position sensors, Ignition Module, Cap, Rotor, plugs, wires, and its still does the same thing, can anybody help please???
Thanks
Rod

 

[rpruski]

Re: Stalling on trottle up

Forgot to mention I also change the water seperator, and the fuel lines, and another thing i noticed is when i start to throttle up the engine rpm goes up, then the injectors stop pumping like someone turned the key off, NEED HELP PLEASE!!!!

Thanks
Rod

 

[wellcraft-classic210]

Re: Stalling on trottle up

Have you been able to monitor fuel pressure. Could be the fuel pump or a restriction in the lines.

Their is most likely a check valve in the barbed fitting coming off you fuel tank pickup. Those are notorious for catching larger debris pieces & causing flow problems.

 

[rpruski]

Re: Stalling on trottle up

I had that off and didn't notice anything is there a way to clean the check valve or do i need to buy a new one?

 

[wellcraft-classic210]

Re: Stalling on trottle up

It should be easy to claen and large debris can be seen lodged around the ball is its present.

A little compressed air blown in the direction of the fuel flow wont hurt & is an added check.

 

[rpruski]

Re: Stalling on trottle up

will this check valve cause the injectors to stop pumping, i can watch the injectors stop as i throttle then the engine dies

 

[wellcraft-classic210]

Re: Stalling on trottle up

If anything is restricting flow by effectively reducing the lin size-- Yes it could cause that sort of problem.

I would inspect the check valve ( clean if needed ) & resuse it unless you see damage.


( I am assuming you have a throttle body based on your ability to see the fuel flow )

As stated above It might be a good idea to monitor the fuel pressure / if thier is a restriction, fuel pump or fuel regulator issue that will show up on a pressure test.

( Be careful to ensure any pressure thesting setups are not leaking fuel as that is a fire hazard )

 

[rpruski]

Re: Stalling on trottle up

yes i do have a throttle body, I cleaned the check valve didn't see any debris, put it back together started fine throttled up fine shut it off waited a few minutes started again, and its doing the same thing again, not sure how to put a fuel presure gauge on it, it has high presure lines with no stater valve hook up, any ideas???

Thanks
Rod

 

[rpruski]

Re: Stalling on trottle up

can anyone help me the fuel line from the tank to the diaphram fuel pump does not seem to have alot fuel in the line when I remove it, could the diaphram pump be bad. Any help will be helpful??

Thanks
Rod