TPI86TA

I just purchased the walbro 255 HP LPH fuel pump to replace my stock pump that failed. Now i was curious on what the thing is on the old set up that hooks up in the fuel line right after the fuel pump itself. My pump came with a plastic type piece of clear hose and 2 clamps. Do i take this device out and do away with it and just use the clear hose? And does anyone have any tips or info on replacing this. My pump came with no instructions. I do have the tank down and im ready to go. Also do these pumps run a lot quiter, and is i t possible to accidentaly hook up the wire wrong and have the pump backwards then. I tried and so far the cars not starting and my pressure at the schrader valve isnt much at all. Thanks...Al in NJ.

Jay

iTrader: (2)

My 2 replacement pumps were plug and play type deals so I didn't have to worry about the wiring. Mine were both louder than stock.
That thing you are talking about is for noise I think, it's not needed... though I'd be a little concerned with the clear plastic tubing. Where did you get the pump?
Whatever is used should be fuel rated for being submersed.

vipershark11

iTrader: (6)

there should just be a piece of black hose that goes from the top of both pumps to the metal fuel lines which the clear hose is for but like the guy above said make sure it can withstand being submerged in fuel ive never seen clear hose used. and my walbro also came with a plug and play harness so i cant really help there. the new pump goes in just like the old one came out.

TPI86TA

I got the fuel pump from http://www.walbrofuelpumps.com/ and it didnt even come with directions. I figured it should be pretty self explanatory, and it did come with a harness you just had to wire the 2 wires in. Which im almost positive i wired it correctly. When i did get some partial directions emailed to me they didnt give me all the directions, and it didnt say anything about the clear plastic tube. Which my only guess is to take out the part in the fuel pump assembly and replace it with the clear hose. In stead i inserted the outlet end of the pump into that part (i have no clue what to call it) just like the way the old pump was. Im wondering if theres so much fuel pressure from the pump that its just squirting out in the tank and not going into that part like its supposed to. Im really confused. I have no clue what to call this part, its recatangular shaped and reminds me of a master cylinder cap or something. If anyone has pics of how their fuel pump looks all hooked up in the assembly, id appreciate it.

I know with the car in the acc. position, the pump should pressurize the fuel rail. I dont have a pressure tester but i did press the schrader valve and only a little trickle of gas came out and not a squirt. I figured it should squirt considering it should be 40-47 PSI. Thanks...Al

305q_ta86

iTrader: (1)

I think the walbro MIGHT be a little louder than stock, but not by much..

TPI86TA

AHhhhhhhhhhhh Haaaaaaaaa......Now i know. After a lot of searching, i see the mystery part im talking about is the pulsator. And that should be taken out and replaced with the plastic hose from what i read. Ill try that and see if it makes a difference.

TPI86TA

With the walbro pump i also hear the pump wont build pressure unless you take out and bypass the pulsator. Its all making sense to me now. Hopefully this will do it.

Jay

iTrader: (2)

I had an issue with mine where the hose clamps came loose and I was losing fuel pressure.
I got mine from http://www.autoperformanceengineering.com/ and it came witha wire harness that plugged in on both ends.
But yeah that pulsator was what I was thinking of, couldn't remember the name.

TPI86TA

I think im also realizing that the fuel pump pressurizes just enough for the car to start with the key in Acc. position. And im guessing the 42-47 PSI isnt achieved until the car actually starts. Can anyone confirm im correct on this?

Jay

iTrader: (2)

the ecm energizes the pump for 2 seconds before startup. it should reach full pressure

TPI86TA

Just great. When i press the schrader valve i only get gas pouring out and not squirting out. Is this because im not pressing it as soon as i turn the key?

TPI86TA

Although it reaches full pressure, does it hold the pressure?

jaykar

iTrader: (1)

It should hold pressure for awhile.
Mine will hold pressure for a few hours.
If it doesn't hold pressure at all, two things to look
for are, Regulator diaphram and leaking injectors.

HTH

Later

TPI86TA

Would a bad fuel pump assembly gasket cause a problem at all? I never got a new one with my fuel pump. I did get a fuel pressure tester now, and im going to see what it says. Thanks

vipershark11

iTrader: (6)

i only think that gasket would cause fuel vapors and maybe a bit of fuel to escape if anything thats worst case scenario since theyre usually fine if you reuse them. pretty sure thats not your problem.

TPI86TA

Well i tested the fuel pressure from the schrader valve and when i put the car into the run position, the pressure went up slightly one time. Up to maybe 2-5 PSI and then immediatley dropped to zero. Other than that every time i put the car in the run position i got nothing at all. I do hear the pump coming on. Any ideas?

TPI86TA

I heard a bad fuel pressure regulator can cause this. Any way to test it? This is a project car i bought that wasnt running and sat for a long long time before i bought it.

jaykar

iTrader: (1)

As old as it probably is and sitting for a long time I
would just buy a new diapram for it.

At the same time if knowledgable, could convert it over
to adjustable and new diaphram.

If not, would get a new AFPR and be done with it. Several
companies make them and good tuning tool as you progress and learn.

Last diapram i bought was about 35 dollars. New comlete
regulator going to be just about impossible to find and if you do, it also been sitting around for 20 plus years.

HTH

Later

TPI86TA

OK. Heres the update. I see 2 fuel lines. One goes to the regulator and one goes to the fuel rail. I followed both lines to where they have fittings and flexy rubber lines near the alternator area.

I disconnected the fittings on the top line ,which I followed, and it ran to the fuel rail. I pressurized the pump and fuel came pouring out of the line. So then i reconnected it. Does this mean im getting fuel to the system properly?

Next i disconnected the fittings for the bottom line, which i followed and it ran to the fuel pressure regulator. I turned the key to pressurize and not a drop of fuel came out of the line. I then reconnected the line. Is this the return line???

Next i pressurized the system by jumping out the wires on the fuel pump relay. I then pinched the section of rubber hose on the line that heads to the regulator. I noticed a slow rise in fuel pressure. It made it to 32 PSI in about 30 seconds and then held steady. As soon as i pulled off the jumper wire, my PSI slowly dropped to 0 PSI in a matter of 30 seconds.

So, does this mean the regulator should be the culptrit?
Is the return line, the line that runs to the regulator?
Is the supply line, the line that runs to the fuel rail?

I know some of these questions may sound stupid, but im just now learning about these fuel systems on these cars since this is the first time i ran into something like this. Any help is greatly appreciated. Thanks....Al in NJ

TPI86TA

???

glock

pull the vaccum line off the regulator ...if there is gas in there you have a bad diaphram

TPI86TA

Right on the money. There is gas in there. I managed to get a Holley AFPR for $50 off craigslist yesterday. Im installing it tomorrow and well se what happens. Thanks for all the help guys.

TPI86TA

WTF SON OF A @#$%^.......So much for a simple task like installing an AFPR. The screws came out real easy with the tamperproof bit. When i went to re-install them, first the tip of the bit broke off in one of the screw heads.To my surprise i got it out real easy. Next a screw began to cross thread on me. When i went to back it out it snapped on me. Just my luck with this car. You guys have any experience on replacing a screw with the head snapped off???

jaykar

iTrader: (1)

Those are very small screws and fine thread.
Your not the first person I know that did that. Repaired
a few and stripped out tamper heads.

Small drill bit and easy out. I used bit and pick with
magnifing glass. I you have to can go oversize and
retap.

My suggestion, take it to a mechanic and when done let him put the cover on
Screws don't take much torque.

Later

TPI86TA

I got one screw out and the other has a long stub sticking out for me to grab with something. Im going to try to grasp it with a pair of small visegrips and turn it out. Then ill have to tap the 2 holes, im thinking of just tapping all 6 holes with a 4m tap and using bigger screws and being done with it.

TPI86TA

Finally fixed the regulator screw issue. Of course theres a catch, the Holley Diaphragm leaks. I had gas coming out of the vacuum port and the adjustment ****. So i put the stock unit on for now and no more leaks. Now i hear the relay kick on and off when in acc. position and still no fuel pressure. When i jump out the relay so the pump has constant juice i immediately get full pressure. As soon as i pull out the jumper wire i figured the pressure should hold, but it doesnt. It quickly drops right back down to zero?

Could i also have leaking injectors? And does anyone know how to test them? If anyone has any idea what else could be going on, something else leaking? I dont smell or see any gas leaks.
----------
Also, when the car is in the acc. position, the relay clicks on and off every 5- 10 seconds. I also sometimes hear a clicking noise of some sort coming from the area left of the injectors? Any ideas? Thanks...Al

TF34MECHH

I had a situation similar to this. The rubber was not torn and the injectors were not leaking but still would not hold pressure. I found out that the disc at the bottom of the FPR that seats onto the hole for bypass was for some reason not seating flush. There was a half shaped moon indentation on it. I swapped it out with another one and made sure I tightened it evenly all around so that it would be seated straight down. Not sure if this helps but look at the seating surface.

TPI86TA

Well i checked out everything again and if i pinch the return line and put the car into acc. it builds up full pressure and then after a couple seconds all pressure drops. The fuel pressure must be going somewhere. When i bought the car the plenum was off and the fuel rail was unbolted. If someone had the fuel rail off, could a bad o ring cause this?

TPI86TA

I also noticed a little bit of dampness ontop the fuel pump assembly. Im guesing a pinhole leak i cant see. Seems to almost be under the electrical connector. Something like that wouldnt cause no fuel pressure would it?

TPI86TA

TTT

TheScaryOne

iTrader: (3)

You put the factory FPR back on? The one that you had already decided was bad? The Holley units are rebuildable. Call them and order a new diaphragm.

It goes like this. Gas gets pumped out of the tank, and that's happening, because if you crimp that line, you get pressure. Gas goes into the fuel rail. If you were losing 40 PSI of pressure instantly, you'd notice it if it was an o-ring, and I doubt any of your injectors are bad enough to instantly lose full pressure. Once pressure is built up, it's up to the FPR to decide whether it goes back to the tank or not. The fuel system is pretty easy, you just have to break it down and troubleshoot it. I think it's probably your FPR.

TPI86TA

I actually put a different used stock regulator on that i got from a friend. I assumed it was good since no fuel leaks out of the vacuum port. Im gona have to check the bottom of the fpr.

TheScaryOne

iTrader: (3)

I also supposed that the part of the pump that doesn't let gas go backwards through it could be bad. But that's hitting something I don't know about. Did you ever get all of the parts you got hooked up and everything?

TPI86TA

Yea installed new fuel pump and all.