Ok guys some of you may remember recently I was concerned about some fuel pressure issues up top but the car over all ran ok. I replaced the existing factory pump with a new racetronix unit now when ever I start the car afer letting it sit for a long period of time the car will lose its prime and not start I have to prime the pump twice to get it to turn over. I know the pressure regulator is in the tank and I followed the instructions to the T is the regulator problem something with the pump or is it in the fuel module itself?

 

I'm gonna take a shot in the dark,reg or check valve.
the one in the tank.

 

The Walbro pumps take a little longer to prime.... this is normal.

As for pressure loss, you need a gauge to see how the pressure holds after you shut the car off, this will tell you if there is a leak somewhere.

Regulators generally hold pressure for a long time, but as they age,it is possible to bleed off after a while. Nothing to worry about if you lose pressure after a couple minutes, but it will take time to build the pressure back up.

 

so bleed off is normal/ok?
could this bleed off be caused by a worn/bad regulator, which in return also could cause a pump "BLEED OFF" under WOT?

 

I have had a racetronix pump before and this is much different they may take a second longer but this is 4-5 seconds to turn over and after sitting over night it wont even do that I'll have to prime it a couple times.

The first racetronix kit I had worked just like the stock pump I never had to prime it and it always started on key. The issue here is that it was literally working just fine with the old pump however my nerves got the best of me and being that the old pump had 125k on it I decided to replace it. On friday the car drove just fine and never had to be primed after sitting I installed the new pump and now I have an issue this would lead me away from the regulator and more towards the new pump.

Since the original post I got a pressure tester at autozone and tested the fuel rail upon start up I have around 60 psi however after turning the key off it will bleed down to about 20 and even lower over time. So either I have an internal leak in the tank somewhere or the check valve in the pump is bad. Once again a bad regulator could cause this but for it to be working just fine with the stock pump and then to have it fail right when the new one went in is too much of a coincidence.
I have contacted racetronix and they instructed me to prime the pump in fuel with it out of the car and inspect the plastic hose to see if it leaks which I will be doing tomorrow.

 

ok I just did the pressure check again.... This time I took the bucket out and set it in a pale of gas and put power to it when the pump kicked on fuel shot out of the top orifice on the pump for a second or two this was not the venturi tube or the flex fuel line port I did it twice to make sure. I dont know if this is normal so please advise.

Anyway the psi on the gauge went to 90 for a split second then bled down to about 75, over the course of the next 45 minutes the psi bled down to about 35psi I watched the pump the whole time no fuel leaked from any of the hoses at any time and the fuel regulator did not leak fuel either. once again i never had this issue with my old pump (except for it losing psi at 6500 rpms) and the odds of the regulator going bad the same day I replace the fuel pump are highly unlikely in my eyes.

I've bought a couple racetronix pumps before and never had an issue I would just like to get this resolved and swap in a new pump as I really feel like there is a bad check valve in the pump.

 

what orifice lol
pic????
im a bit blonde from time to time.
there should not be any leakage of any sort though.

 

Sounds like you deadheaded the pump, which you should NEVER do.
I am guessing that you did not leave the factory fuel lines connected when you tested it.
That other hole is the pressure relief that prevents pump damage.

If it takes a few minutes for the pressure to fall to zero, the regulator or pump is not bleeding off enough pressure to worry about.

FYI, never operate the pump out of the tank in a bucket of gasoline. One spark & you may be living in a burn unit at the nearest hospital.

 

I was told by the racetronix support board that this is the easiest way to test the pump out of the car and is exactly what I did. Submersed the pump in gasoline and plugged it into the factory harness and turned the key with it dead headed to a pressure gauge. I'm not saying it was smart but it was what they told me to do.

Also regardless of how long it take to bleed off pressure it still shouldnt be doing that. The fact that it is bleeding off pressure down to 35 psi and still falling would explain my hard starts after letting the car sit over night. While I know it isnt a serious issue I still dont want to have to prime my car every morning after I just installed a new pump. I have used racetronix pumps before and havent had this issue.

Once again heres how I look at it my old factory pump still worked it just fell off at 6500 rpm a bit. But every morning the car started right up on the first crank and was ok. The last day I had that pump in was Friday that day I replaced it with a racetronix pump this is the ONLY thing that was changed and now I have a problem with hard starts every morning or even letting the car sit for a while and after seeing it bleed down to 35psi is evident that something is wrong. The odds of the regulator starting to leak the day that I put the racetronix pump in are pretty slim i think anyway.

I hope I didnt come off rude or anything but you all have to understand where I'm coming from going from a factory pump that didnt have this issue to a new racetronix pump and having this issue and then having people tell me its not the pump or its nothing to worry about is just getting a little old. I have since ordered a new pump btw but this is still frustrating

 

i was having some of the same issues and after all the research and phone calls i replaced the plastic tube with a pc of GATES SUBMERSIBLE 5/16 hose and some efi hose clamps and now i hold my pressure and my prime is still at 55 as well.

 

i stand corrected on the prime it did fall....but i turned the key on and it instantly went to 60psi
i will check in the morning

 

I gotcha from what I understand some falling is normal and ok but it should not be enough to cause a hard start which is what mine is doing. At any rate this is the first ractetronix ive had a issue with so if the new one i ordered has the issue ill keep your idea in mind. I did check the house over 3 different times when it was primed and couldnt find any leaks

 

good luck..
my next test was going to be the fpr,then the rail,then last the injectors.
keep me posted

 

ya man I wont have an update till this weekend when i get the new pump but btw what aeroquip hose was it? the braided staineless one? and it was 5.16 ID right?I dont know what your case is but in mine I dont see how it could be the fpr or the rails seeing as it worked fine the day before with the old pump

 

aeroquip push loc hose.
i hear ya..
i made the hose a tad bit long so it would help push the punp down and to where i had to slightly push down on the module,and still allow it to lock in place. (lock ring)
aeroquip is not recommended,it is not a submersible fuel line.
Gates: PN 27097 is a submersible "rated" SAE J30R10

 

Hate to poop on your parade, but that amount of pressure drop is perfectly normal. My stock pump did it, and so does my new Racetronix pump. As a matter of fact, my pressure falls off faster than yours on the initial prime, and after a couple of minutes is around 20 psi at the rails on mine (my regulator is up front though). As soon as I bump the engine over, the pressure bumps right back up to 50+ psi, and when it fires, 58 psi. No hard starts whatsoever, so you likely need to look elsewhere for your hard start issues.

 

its ok thanks for the reply anyway I have a new pump on the way so we'll see if it changes everything its just common sense would tell me that since that is the only variable that changed since I had an issue that it would be the problem if not I guess it could be the fuel pressure regulator but what are the odds it goes bad on the same day

 

Aftermarket pumps are very hit or miss...the first Racetronix I installed failed after priming it a few times (never even got to start the car). I ordered a new bucket assembly and had Lonnie install a new Racetronix pump in it for me so I could just drop it in, and that one has worked well for a few weeks now (that's as long as I've had it installed).

It sucks, but I'm quickly finding that fuel systems are very finicky.

 

ya i hear ya ive searched the topic countless times on here and people have isues but very rarely ever figure out the problem so hopefully the new one will fix it. I had one of these in my old firebird and it worked fine until i sold the car. I mean what else could it be other than the pump lol for it to literally wrk fine with the old one and now hard start with the racetronix

 

well i got in the car this morning and the gauge showed zero,turned the key on and gauge went straight to 60 started the car on first try with no hesitation either.
i do have a voltage drop at wide open throttle do the the pump drawing to much power from the alternator.
FIX
i am going to install a truck alternator and the hot wire kit.
then back to the dyno for the final tune