4.3lx carb 2 barrel

[Gkelly]

I installed a new carb ran great first time out no issues, the second trip it started loading up at idle. Once it shut off it will keep pouring fuel. I got a new fuel pump and still does it.
The pump I got was a Mercruiser part # it said 9 to 10 psl
I believe I have to much pressure forcing fuel thru carb

What is the pressure supposed to be

[mmwjr]

Do you have a mechanical or electric fuel pump? Mechanical one can’t put out much above 7 psi. Your issue could be the float set to high.

[Gkelly]

Its a electric pump oem part #

[jrsick]

Agree that carb float is highly likely cause.

[Gkelly]

Ok thanks, ill tear it down and check the adjustment

[mmwjr]

The OEM pump is set to the correct pressure so I would check the float height.

[jparsons121]

+1 on the float.
.
Test the float to be sure it really floats. I had a similar issue because a replacement brass float had a pinhole and filled with gas. Another carb with a newer foam style float also wouldn’t float, it was just saturated with gas.
Check the needle & seat to be sure its in good condition and operates freely. I usually blow into the fuel port and move the float up and down to check if it stops the air flow.
Note: some carbs give a measurement with the gasket others don’t. That can Make the difference of it working properly or not.

[Gkelly]

Thank you I will check all of it.
Its just weird cause the original carb did it and now the brand new one does it. I have a kit on the way.
Can anyone say what the setting is for the float.
Thanks again everyone.

[donald]

It should be in the information that comes with the carb.
Don

[Gkelly]

Just checked fuel pressure on new pump its 11-12
Is that correct
Or do I need a regulator to put it around 5-7

[mmwjr]

Originally Posted by Gkelly

Just checked fuel pressure on new pump its 11-12
Is that correct
Or do I need a regulator to put it around 5-7

7-8 psi should be the max for a carb. Is the 11-12 at idle or across the higher rpm? If it decreases with rpm I would leave it alone.

[Gkelly]

Motor off, pressure tested straight off of pump.
It won't run, too much fuel being pushed thru carb.
Going to rebuild the new carb on monday

[mmwjr]

Originally Posted by Gkelly

Motor off, pressure tested straight off of pump.
It won't run, too much fuel being pushed thru carb.
Going to rebuild the new carb on monday

Ok that’s deadhead pressure since the engine is off, I’d leave it alone and address the carb as you plan to do.

[Gkelly]

Will do
Thanks

[Gkelly]

Ok guys rebuilt new carb.
Turned over then immediately flooded out over top of carb.
I'm lost at this point any other suggestions.

[mmwjr]

Did you try as jparsons suggested of blowing air into the fuel inlet and move the float to see if it stops? I still thinks the float is not set correctly or the needle valve isn’t sealing.

[Gkelly]

Well, I actually forgot to do that, I will check that tomorrow, I set the float to specs in the instructions, 14mm closed and 27mm open

[jparsons121]

Based on your spec’s, I’m guessing that this is a 2-bbl Mercarb. If so, the settings do depend on where you measure to and which needle you have.
For the spring type needle, the 14mm is correct. If you have the solid needle, it’s only 10mm. Also, the gasket needs to be included in the measurement and the point on the float isn’t the bottom of the ‘toe’ it,s the dot on the side of the float.

See the following if it’s a Mercarb. (Same details will apply to others as well).
https://www.carburetor-parts.com/assets/images/K529.pdf

[Gkelly]

Yep it is a 2 barrel, and spring needle, I did all the settings just as you said.

[jparsons121]

Did you do the test on the float to see if it really floats? Also, brass or poly float?