why does my fuel filter drain back?

[datguysaL]

why does the fuel filter drain back on my truck? the carburator is a edelbrock 750, 1411. and has a mechanical pump.

ive been having to pump the pedal a few times to get it to start, so i intalled a clear glass inline fuel filter and noticed that when i cut off the truck, that the fuel drains from the filter. and that is causing it to crank a few times and me pumpin it to get it to start..

why does the fuel drain out of the filter? or what can be causing this??

thanks guys.

[78 Chevyrado]

When mine did that it was a bad diaphram in the fuel pump. it was draining back to the tank.

[datguysaL]

is there a way to test the pump without having to pull it off?

[spinem]

its easy to take it off... those glass washable screen filters restrict sooooo much..... switch to a fram g3, gurantee ull feel the difference... also check that the clamps that secure the filter are tight. air can go places liquid cant.

[datguysaL]

yeah, i just didnt want to replace the pump without being sure that was the problem. i installed the clear filter just to see if gas was flowing thru the line from the pump, i was kinda liking the way it looks, but ima finish checkin the clamps, hoses and all the small stuff first think tomorrow. thankx guys, ill post up what the problem was, once and if i find it.

[spinem]

good luck!

[Shamil]

I'm Having the same issue.... i replaced the houses and clamps days ago, nothing happen still same problem , yesterday i replaced the fuel pump, with no luck...

any other idea..

the carb is a Monojet 1bbl

[Eighty-6]

I think I may be having the same problem or was having it before I parked it to take the interior out. I have to do the same pump it and turn it over several times before it turn it on but this is usually every couple of days so not sure if that matters.

[KazuyaIB]

I have the same problem with my 86 after I installed the TBI. On mine everytime i switch the tanks the valve makes alot of noise. Have to crank to get that gas up if truck is left alone for a couple of hours

[theprestongroup]

I am having the same problem with mine. I am considering putting one of those $40 electric fuel pumps at the tank in front of my mechanical fuel pump. Maybe that would help with starting.

[datguysaL]

hey guys, ok, so today i went at it again. tighten all the clamps and made sure all the hoses were on good and not cracked...

no leaks anywhere, and no leakage from the pump seep hole either.

so...

i started the truck and i quickly shut it off and pulled the gas line from the carb and plugged the hose before the filter drained back.. and i waited for like about 10 minutes, and the filter did not drain back this time...

i did this 2 times and it didnt drain back.

so my guess is that my floats are stayin open. from my understanding, the fuel line into the carb should should not loose vacuum when the engine is off. so i hooked up a handheld vacuum pump to it and pumped it once and the vacuum would not hold.

my carb is an edelbrock performer 750cfm 1411. i think these have an adjustable float. ima try that tomorrow. ill let yall know if that works...

[datguysaL]

Originally Posted by theprestongroup

I am having the same problem with mine. I am considering putting one of those $40 electric fuel pumps at the tank in front of my mechanical fuel pump. Maybe that would help with starting.

if u plan on using the electric fuel pump, you might need to also install a fuel regulator. i wouldnt use both pumps in series. just use one or the other.

is your truck carb or tbi?

[wheels67]

yes. the trucks should start right up even if the filter level is lower because the float bowl should maintain a level amount to start vehicle without pumping. Improper adjustments or worn floats wil cause this.
And of course for easy starting the choke butterfly has to be functioning properly...which is unrelated to fuel level of course...

[cableguy0]

Its normal for an edelbrock. The fuel is boiling out of the bowls. A 1 inch spacer will likely cure it. One of the many quirks with the edeljunks.