Fuel Pump seal

[rpeterslll]

I have a 2000 2dr 4x4 blazer ZR2.
I just replaced my Fuel pump last weekend and its working great. Since I replaced it I went to fill the tank all the way and I had a problem. Since the pump didn’t shut down automatically I seemed to have overfilled my tank and it was coming out of the top of the tank, I assume its where the fuel pump is mounted.

When installing the fuel pump I used the rubber O ring around the pump and I secured the pump down with the metal cam ring that was used with the old pump. It seemed to be a tight secure fit but it seems as though there wasn’t a good enough seal since fuel came out the top of it. What should be used to be sure there is a tight seal on the fuel pump and the tank?

[mike2004tct]

It sounds to me like you have 1 of two possible problems.

1) you might have pinched the round rubber gasket between the tank and the pump housing (Did you keep the old gasket?)

2) the pinch fittings on the feed line and return line may be leaking,causing gas to drip onto the top of the pump housing.
This is the problem I had on mine. I had to buy new fittings to correct
the problem. (Napa carries them, they're two different sizes)

[rpeterslll]

Thanks.
I can check the gasket to be sure its not pinched, is this all that keeps fuel from leaking out the top?

This wasnt really a leak, but the fuel was pouring out the top of the tank and falling on the ground in a large quantitys.
The gas pump at the gas station would usually shut down automatically when the tank is full. Does it do that from back pressure? would there be a lack of pressure if there was a gap between the tank and the top of the pump housing?

Thanks,
Rob

[mike2004tct]

Originally Posted by rpeterslll

Thanks.
I can check the gasket to be sure its not pinched, is this all that keeps fuel from leaking out the top?

This wasnt really a leak, but the fuel was pouring out the top of the tank and falling on the ground in a large quantitys.
The gas pump at the gas station would usually shut down automatically when the tank is full. Does it do that from back pressure? would there be a lack of pressure if there was a gap between the tank and the top of the pump housing?

Thanks,
Rob

The pump at the station will shut off as soon as gas back-washes into the nozzle. Most likely the gas pump nozzle is defective.

As for the truck tank, that round pump housing seal isn't the only place that gas can leak out of. The pump housing itself is plastic and has 3 fittings on it; Feed, Return, and Vent. The Feed and Return lines are under pressure from the pump and could leak if the pinch connectors I mentioned earlier are bad.

By your description, I'd guess a bad mating between the pump housing and the gasket, or else the pump housing itself is cracked. Unfortunately, you'll have to drop the tank to find the problem.
Mike

[BlazerLT]

If the fuel is leaking out of the driver's rear of the truck, you have filled the charcoal canister with fuel.

[rpeterslll]

Whats the Charcoal canister? The fuel comes out of the top of the tank in the back of the car, not the drivers or passengers side.

[BlazerLT]

Originally Posted by rpeterslll

Whats the Charcoal canister? The fuel comes out of the top of the tank in the back of the car, not the drivers or passengers side.

The EVAP canister.

Did you make sure all the lines where connected back in?