Ls1 prime no pressure

[gasman]

I have a 94z with a 2000 ls1 in it. I have had problem since the swap its always had a hard start up...but I just installed fuel a pressure gauge and I noticed I don't have any fuel pressure after the pump primes...once it gets started no problem.... When I turn the key pump primes motor turns over and after a few seconds it starts and runs no problem.... I have a new fuel pump.... Oh yeah I'm running Lt fuel line and the corvette fuel regulator.... Any suggestions on what this could be....

[hoogiesngrinderz]

Usually it's the check valve in the pump.

[gasman]

So I will possibly need a new fuel pump???? Or is there a separate piece I can buy..... BTW I'm using all the lt1 in the tank just swapped pumps I'm running a walbrogh pump

[1BADAIR]

how do you have the vette filter in they lines?

[gasman]

It's up front right near the air filter....

[hoogiesngrinderz]

So I will possibly need a new fuel pump???? Or is there a separate piece I can buy..... BTW I'm using all the lt1 in the tank just swapped pumps I'm running a walbrogh pump

I have the same issue with my brothers truck that I swapped to TPI. I used a Walbro 255 and it leaks down almost instantly through the pump.

When I built my NBM 98 Z28 I was having pressure issues right before it got side swiped. Dropped the tank and put in a Racetronix pump which completely blew out the regulator...my problem in the first place. Fixed the regulator but still lost pressure fast, the only reason I haven't put the pump in my red Z28

[gasman]

Sounds like the walbro pump doesn't have a check valve.....

[hoogiesngrinderz]

Hit and miss from what I hear. I'm 0 for 2. Well, 0 for 1 and who knows with the Racetronix...my fuel pressure was almost 66 psi at idle even with the bad regulator, just didn't hold pressure. Stock should be in the 56-58 psi range.

[gasman]

So there's really no sure fix for this lol .... I'm gonna assume there's no harm being done to the motor with this issue other than being annoying

[gasman]

So there's really no sure fix for this lol .... I'm gonna assume there's no harm being done to the motor with this issue other than being annoying

[Gearhead4life]

it shouldn't bleed down that quick, my walbro 255 takes about 25 mins or so to bleed down from 60 lbs prime pressure

[WMCCjames]

It depends on the pump. I have been running a Walbro 255 for over 10 years and it leaks down as soon as it stops running. Been like that the whole time. No harm. Just turn the key, let it prime for 3 seconds and then engage the starter.

[1BADAIR]

Just cycle th key once before cranking