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Author Topic:   The unexplainable
Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-15-2001 04:10 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Man, Im really getting P***ED off!!! I still cannot maintain fuel pressure, yes the gauge is good, it doesn't matter anyway as the car runs out of fuel with the gauge or not. Anyway,
1. Iv'e pressure checked all my lines and they are good
2. Iv'e replaced fuel pumps and regulators three times.
3.Iv'e triple checked my fittings for cracks-they are good.
Heres what happening that is unexplainable to me.
Iv'e primed the fuel system, tank full of fuel.
I run the car for 10-15 mins and then the fuel pressure keeps dropping, when doing so the pump sounds like it's staving for fuel to pump. Tank is vented and pump is below the tank.
When I turn off the pump after either running the engine or not lots of air bubbles return to the tank???? Where the H*LL can it be coming from???? It seems like the longer the pump runs the more air collects, it also seems like the pump is pulling air in from the pump housing somehow. Man, Iv'e done all I can do other than try a different brand pump.
As soon as the pump is shut off bubbles come back into the tank instantly. Tank outlet fitting not split cracked or other.
12 days of working on this with no changes what so ever. For the first 10 mins of the day running the car it runs fantastic then it dies slowly because it runs out of fuel.
I have exuasted all ideas. When I bypass the cars fuel system completely (tank and lines)and the same think happens Im just out of ideas as to why.
Im totally bummed out, my car is completley done, runs great, but can't drive it only because of this fuel problem--and that I can't seem to fix or understand why

[This message has been edited by Gary (edited 12-15-2001).]

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Greg Pettit
Journeyman

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From: Dallas, TX
Registered: Nov 2001

posted 12-15-2001 04:19 PM     Click Here to See the Profile for Greg Pettit   Click Here to Email Greg Pettit     Edit/Delete Message   Reply w/Quote
I do not know your setup, but where is your pump mounted? Too far from the tank=vapor lock. Any restriction in the pickup will make this worse. Make sure the fuel line from the pump to the tank is not next to any heat.

I hate these pain in the a$$ problems.

Good luck,

Greg P

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Moneymaker
Administrator

Posts: 11493
From: Lyons, IL, USA
Registered: May 99

posted 12-15-2001 04:49 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
Well Gary, you can always convert it over to propane. j/k
I have one last test for you if you have the inclination Gary. Take the pump and a fuel source (jug is good) and run a separate line fron the jug to the pump (off of the car) and then a separate line to the regulator to eliminate the lines on the car and the tank altogether. You do have the regulator mounted near the carb don't you?

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Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-15-2001 05:59 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Alex, tried that already--same problem Although my regulator is on the fender apron on driversdie and carb lines on the passengerside as the carbs are flipped backwards as Ford used to do.

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Moneymaker
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From: Lyons, IL, USA
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posted 12-15-2001 06:24 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
OK.

------------------
Alex Denysenko
Co-Administrator and Moderator
NHRA/IHRA/SRA member
NHRA and IHRA SS/LA National Record Holder '00 & '01
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Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-15-2001 07:17 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Alex, this is why im baffled, iv'e tried I think every test and change of parts. I even replaced a few of the hose ends thinking there may be a hidden crack but nothing I do or test makes the problem better or worst. I wish I couls find a leak or something so Id know where to remedy the problem. At first I thought the reg. was bad, then tried replacing the pump--then twice. Finally I decided to return the blue and up-grade to the black pump. After doing all of that and still not change I eliminated the the possible problem there might be in the lines system of the car by running the car from a 5 gallon gas can and external fuel line direct to the reg. When that didn't help I double checked again the voltage at the pump and the relay and both were good. Now Iv'e about run out of ideas to try. For as basic as a fuel system is this gremlin in my car is a real bitch to find-GRRRR!!!

Dear Santa: PLEASE, all I want for Xmas is my fuel sytem to work right

[This message has been edited by Gary (edited 12-15-2001).]

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Moneymaker
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From: Lyons, IL, USA
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posted 12-15-2001 07:20 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
Hey Gary, one last thing to try. How about lowering your floats a bit?

------------------
Alex Denysenko
Co-Administrator and Moderator
NHRA/IHRA/SRA member
NHRA and IHRA SS/LA National Record Holder '00 & '01
Fleet of FoMoCo products
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Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-15-2001 07:40 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Alex, I could try that but have them now just below the sites abit. What doesn't make sense is how air bubbles come back up from the pump when shut off. It's like the car runs out of gas at the pump inlet but the pump is lower than the tank! Theres no obstructions in the inlet tube either. How can air get into the system if all the lines have been tested as having no leaks?
Seems like the pump is cavitating like a boats propeller so it can't push fuel. Even when tested with clear hoses in and out with lines containing only fuel you can see air bubbles forming and they collect around the inlet hose at the pump fitting but thats sealed for sure trust me. No cracks in pump housing from over-tightening. This is werid and defies everything Iv'e learned. Can air be somehow drawn in from the pump other than the inlet/outlet? Are these pumps somehow vented?
I seriously doult three new pumps could be bad but the problem is exactly the same with either of them installed or the regulators.
Seems if theres air getting into the system there would also be a leak somewhere but there are none. Heck, Ive even replaced the fuel pump fitting too, added sealer to treads, teflon, teflon and sealer,tried different fitting with just a rubber hose too with double clamps...still the same air bubbles coming back to tank!!
(Pounding head on wall at this point)

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steve'66
Gearhead

Posts: 3653
From: Sonoma,CA,USA
Registered: Mar 2000

posted 12-15-2001 09:42 PM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
Gary,

I've been following along with your predicament, and don't have the answer either. But if I were you I'd take two steps back and look at the big picture. It's something real simple and stupid! Your fuel system is adequate to run 8 second quarter mile runs back to back, and you know all the components are fine. I can't explain the air bubbles, but I've never looked for them either. Maybe all fuel pmps cavitate when they "dead head" and fuel isn't flowing. Isn't that why the carb's bowls are vented? Your engine should run for several minutes just off the fuel in the bowls, especially with 2-4s. Assume the fuel delivery is ok and look for something else. I might me all wet, but that's what I'd do. How about trying a boat gas tank temporarily positioned above the carbs and gravity feeding the carbs? It'll keep up and will totally eliminate the fancy fuel system. Good luck,

SteveW

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chips67
Gearhead

Posts: 537
From: louisville, ky, usa
Registered: Jul 2001

posted 12-15-2001 10:59 PM     Click Here to See the Profile for chips67   Click Here to Email chips67     Edit/Delete Message   Reply w/Quote
is the tank vented? try it with the gas cap off. also could it be trash inside the line that is hanging in the system like a valve and only closing things off when the fuel tries to flow? if you cant find it my dads idea works. i had a problem once and he said look, and he removed the radiator cap and held it above the radiator about 6 inches. he said "replace everything under this", then he screwed the cap back on and said "problem solved".

------------------
67 coupe, 650dp and rpm intake on 5.0 with afr 165 heads, 4 speed, 4.11's.....best so far is [email protected] in 1/8 mile with 1.79 60ft. time.

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clevelandstyle
Gearhead

Posts: 178
From: Connersville, IN
Registered: Jul 2001

posted 12-15-2001 11:17 PM     Click Here to See the Profile for clevelandstyle     Edit/Delete Message   Reply w/Quote
It seems that it always comes back to the fact the you are dead heading the pump. Maybe you should try rigging up a fuel return to see if it helps. I know that there are thousands of cars out there that don't have a fuel return, but it's something to try.
It's like Steve said. It's probably something simple and stupid, but you've got a lot of heads here thinking about it and no one has come up with the problem yet. Maybe we should all come over to your house to look at it. You're in Florida, right?

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Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-15-2001 11:39 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Im sure with gravity flow from a tank over the carbs will work but Iv'e spent over 1200.00 on this fuel system and it's going to be used and work one way or another!!
Nobody Iv'e asked can answer my question as to how air can collect in the pump and back to the tank when I shut the pump off. I can see the lines are full of fuel through the clear test tubing. This happens with either using the fuel cell or by using a complete system outside the car with other lines. The only thing left that is the same is the carbs, fuel pump, or regulator. Each of these three items are used in each test I perform. How can three pumps and regulator be bad in a row? If so Iv'e gotten the worst luck!
NOTE: another thing, when the pressure drops down to 2psi from 6.5. You can try to raise the pressrue at the regulator but it will not adjust higher. Turn the pump off, wait 3-4 mins. after air bubbles run back to tank from the pump and try the pump again...it goes right back up to 6.5psi where I set it earlier then starts to fall all over again beacuse of the air in the pump builds again.
I primed the whole system may times as well.
Like was stated, when pressure remains fairly constant the pump starts to cavitate losing pressure, maybe a deadhead system just won't work but whay not when other use them with the blue and black pumps?

Rememeber guys, EVERTHIING relating to the fuel system is brand new and clean as a whistle. Now another half of the new system has been replaced three time. At this point it isn't the money anymore....it a damned quest and don't care what it takes to fix the problem!!!

[This message has been edited by Gary (edited 12-15-2001).]

[This message has been edited by Gary (edited 12-15-2001).]

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Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-16-2001 12:00 AM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Yes Im here in FL. sure you all can come over and look at the car I'll buy a KEG/s and supply all the steak and lobster for the BBQ. You have been invited

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steve'66
Gearhead

Posts: 3653
From: Sonoma,CA,USA
Registered: Mar 2000

posted 12-16-2001 12:03 AM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by Gary:
How can three pumps and regulator be bad in a row? If so Iv'e gotten the worst luck!

That's why I think your fuel system is fine! Although it may be overkill! A 5/16" line with a stock mechanical pump would work fine for your street/show thumper car. You could be over powering your needle valves if you're sure the gravity feed system would work fine. You do not need that much fuel to cruise on the street. My daughter's '66 uses a stock 5/16" line and a holley red pump and has never had a fuel problem running 12 second 1/4s. Other folks that I know can run a 1/4 mile drag race with no fuel pressure at all and 2 four barrels! So, all I'm saying is maybe less is more. 5 psi is way more than adequate for your needs.

When the floats are closed on our 351w's 750 holley the clear fuel filter is empty. (yep full of air) I dunno where the air came from, and I don't really care! Take two steps back and think about it Gary. Good luck, your car is AWESOME!

SteveW

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Gary
Gearhead

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From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-16-2001 12:11 AM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Steve, contant low pressure is fine at this point and will accept that but I broke down twice today after the pressure finally when to zero and the car ran Out of gas. Low is ok zero is not. Today I set the psi to 6-6.5 max, the needles should beable to stay closed. Problem is it will eventually drop to nothing and car will quit No lines are near heat an tank is full with no obstructions in the tank, (good vent 1/2" in size.)

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Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-16-2001 12:20 AM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
I would convert back to mechanical pump at this point but not sure I can re-install the ecentric using a gear drive...humm?

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Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-16-2001 07:12 AM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
I snapped a pic of one of the ways the pump is installed. Note: the fuel level is quite abit higher then the pump and the weight of the fuel should always keep fuel to the pumps inlet. Iv'e even tried lowering the pump well past the fuel outlet of the tank with filter removed and still have my fuel delivery problem. With this pictured pump and line arrangment fuel should have no problem getting to the pump.
http://hometown.aol.com/garyslight/page1.html

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Greg Pettit
Journeyman

Posts: 21
From: Dallas, TX
Registered: Nov 2001

posted 12-16-2001 12:11 PM     Click Here to See the Profile for Greg Pettit   Click Here to Email Greg Pettit     Edit/Delete Message   Reply w/Quote
Have you tried plugging one end of the system and pulling a vacuum on it? You'd find any leaks ASAP that way.

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Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-16-2001 12:35 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Better yet, I'll drain the tank again, then I will adapt a tire valve stem fitting on the on the inlet tube of the fuelpump. Then I'll plug the end of the lines to the carbs and fill the whole system with air pressure. I'll then go over every 1" of the system with soapy detergent and see if I find any bubbles forming around any part of the fuel line system, pump and regulator and note any differnces in pressure with air pressure gauge as well. This way it will simulate pressure on the system like fuel pressure instead of vac. Iv'e already by=passed the whole system with other lines before but this way "ALL" the componets will be tested.
Good idea....thanks
Boy...what a pain it the A$$...JEZZZ

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68bbstang
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From:
Registered: Sep 2001

posted 12-16-2001 02:18 PM     Click Here to See the Profile for 68bbstang   Click Here to Email 68bbstang     Edit/Delete Message   Reply w/Quote
Here's my take on your problem. You are focusing on your fuel PRESSURE problem when what I see from your photos is a VOLUME problem. The 2 work in relationship with each other. I'm sure you have sufficient volume and pressure at your single regulator, but consider that it is mounted very high and there are internal flow limits to the regulator. My suggestion is to run LEAST 3/8" up to the motor (you should have full flow and pressure to that point) then mount 2 regulators AFTER a manifold to the carbs. You have pressure (and volume) loss with the head pressure you are trying to have the pump maintain with a single regulator so far from the carbs. One misconception most people have is that braided stainless flows well. Not so. The ID of both the hose and fittings is considerably less (by %) than hardline. I would run .045 wall seamless 304 stainless from your pump to the motor, then use the braided from a manifold to seperate regulators to the carbs.
Good luck,
MW


quote:
Originally posted by Gary:
I snapped a pic of one of the ways the pump is installed. Note: the fuel level is quite abit higher then the pump and the weight of the fuel should always keep fuel to the pumps inlet. Iv'e even tried lowering the pump well past the fuel outlet of the tank with filter removed and still have my fuel delivery problem. With this pictured pump and line arrangment fuel should have no problem getting to the pump.
http://hometown.aol.com/garyslight/page1.html

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Mark T 7724
Journeyman

Posts: 51
From: Palmdale, CA
Registered: Nov 2000

posted 12-16-2001 02:50 PM     Click Here to See the Profile for Mark T 7724     Edit/Delete Message   Reply w/Quote
Gary the bubbles you see coming back are most likely due to cavitation, This can be caused by a number things, Try increasing the line size on the suction side of the pump. Also you need 5 tube diameters of straight tubing going into the pump 1/2" tube X 5 = 2 1/2". One other thing to try is temporarily mount a Holley "Blue" and run a line to a fuel can and see what happens. Cavitation is a phenomenom I see alot in Hydronic Systems it is caused by pressure differences when a fluid passes by a fitting or a venturi, Pressure differences become great enough to allow fluid to "Vaporize", If this happens close enough to the pump it can collect in the pump slowly causing it to lose prime. That is the reason for increasing line size or having a section of straight tube going into the pump. I hope this helps because it sounds like you have covered everything else.

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Butch Jennings
Gearhead

Posts: 340
From: California
Registered: Apr 2000

posted 12-16-2001 03:02 PM     Click Here to See the Profile for Butch Jennings   Click Here to Email Butch Jennings     Edit/Delete Message   Reply w/Quote

Gary,

Have you replaced the line coming from the tank to the pump? I've had a braided hose fitting cut a nice flap inside a hose once that drove me as, well almost, as nuts as you are at this point.

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Butch
460 powered 1967 Comet Cyclone
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Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-16-2001 07:49 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
I checked to too Butch but good point as Iv'e had that happen to me too one other time.
Thanks

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DidgeyTrucker
Gearhead

Posts: 632
From: Nashville, TN USA
Registered: Oct 99

posted 12-17-2001 12:28 AM     Click Here to See the Profile for DidgeyTrucker   Click Here to Email DidgeyTrucker     Edit/Delete Message   Reply w/Quote
I've never worked on a system with an electric pump but I do remember being in a friends car with an electric pump and I remember it shutting off from time to time. Should yours do that when a certain pressure is reached? Yes, I know as an engine runs there will be a drain on the fuel system that would drop pressure and that should keep the pump on.

What does the system do when you disconnect the carbs? Does it constantly deliver the same volume or does it still drop off after a while? If you connect a short line to the outlet of the pump does it still act up?

Just some thoughts.

Tracy

[This message has been edited by DidgeyTrucker (edited 12-17-2001).]

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Mark T 7724
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Posts: 51
From: Palmdale, CA
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posted 12-17-2001 12:35 AM     Click Here to See the Profile for Mark T 7724     Edit/Delete Message   Reply w/Quote
Gary: I thought you were using a "Rotary Vane" style pump, From what I see in your picture that seems to be a "High Pressure" pump for a fuel injection car. What exactly is that pump?

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Rory McNeil
Gearhead

Posts: 557
From: Surrey, B.C. Canada
Registered: Nov 2000

posted 12-17-2001 03:51 AM     Click Here to See the Profile for Rory McNeil   Click Here to Email Rory McNeil     Edit/Delete Message   Reply w/Quote
Actually, Mark, I think you are looking at his fancy alum. fuel filter. The actual pump I think, is blocked in the picture by the tank & diff.Gary, if you unhook the fuel line from the regulator to fuel log, & turn the pump on, does it spray out a couple of feet? or just trickle? You SHOULD be able to fill a 1 gallon container in 10-20 seconds. Can you do that? Definetly a head scratcher!

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78 Fairmont 428 4 speed [email protected]
80 Fairmont 302 5 speed [email protected]
85 Mustang NHRA Stocker under construction, 302 5 speed

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Gary
Gearhead

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From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-17-2001 05:28 AM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Yes when I open a line at one end of the regulator the fuel really flows good! It's when under pressure awhile that you see a drop in pressure and finally it goes to about zero. Turn the key off and wait 5 mins. turn back one and the pressure goes right back where's it's supposed to be then starts falling again soon. Strange all three pumps that iv'e tried do the same thing and voltage is good at the pump @12volts while running the pump... At first I thought it was because I placed the cell with the sump in front and was losing pressure while driving but the problem I have been experiencing also happens just sitting in the driveway.

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Moneymaker
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From: Lyons, IL, USA
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posted 12-17-2001 10:53 AM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
What are the fuel pump part numbers please?

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Alex Denysenko
Co-Administrator and Moderator
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ProStreet64Falcon
unregistered
posted 12-17-2001 10:54 AM           Edit/Delete Message   Reply w/Quote
Gary,

I shared your predicament with several of my racing friends yesterday. Two of these guys have been racing for 30 yrs. The consensus seems to be.

If you are going to run 1/2" fuel line on two 4s you need two regulators. One for each carb. It is a volume problem that one regulator cannot handle. (1 line input into 4 lines output)

Or


If you do not want two regulators. Run 1/2" line from the Fuel Cell to the Pump. From the Pump to the regulator change the line to 3/8" line. That will supply more constant pressure to the regulator and should solve the problem on a car that sees the track ever once in a while.

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Ryan Wilke
Gearhead

Posts: 607
From: Stanton, Michigan
Registered: Oct 2000

posted 12-17-2001 11:18 AM     Click Here to See the Profile for Ryan Wilke   Click Here to Email Ryan Wilke     Edit/Delete Message   Reply w/Quote
Gary, Have you considered trying this -

Re-install the clear test line from the tank-to-pump line...disconnect the regulator-to-carbs fuel line and run it into a clean 20 gal container...run the fuel pump and watch to see if air bubbles form on the tank side with the fuel pumping into the container...I'm not sure if your fuel cell would pump empty before air bubbles start forming in the clear tube, but if it does - then I'd be inclined to think that it is a matter of cativation due to deadheading at the carbs...

Maybe better yet (or easier to do) would be to simply install your cell-to-pump clear test line and install a temporary fuel return line from the carb fuel manifold (log) to the cell and run the pump to see if it would run more than the usual few minutes without producing the air or drop in fuel pressure. If it does not produce air bubbles in the clear test line over the usual few minutes, then try it with the engine running -- I agree with some of the other opinions; that your problem is related to deadheading and cativation.....

Hang in there & stay focused...or these things can drive you crazy!!!
Just my 2-cents worth :/ .... Ryan

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Gary
Gearhead

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From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-17-2001 08:07 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
I tried the pump out of car today just to test it again out of the car to eliminate any problem with the car itself. This time I powered it with my battery charger on a fresh battery out of the car to make sure I had constant voltage. I layed pump on the ground and attached two clear lines, one from a can of fuel, the other line to a T-fitting. On the T, I installed the pressure gauge (new) and plugged the other hole to make it a deadhead set-up. I then powered up the pump and cracked the plug to allow excess air out of out-line from pump so both lines were compeltey full of fuel (NO AIR BUBBLES) Gauge then read 13.8psi. In less than 2 mins. the gauge started to drop, by 3 mins. the gauge read 12psi and soon after the pump and needle was fluxuating from 11-12psi. then a min. later from 10-11, then 9-11psi. Finally after seeing the gauge needle fall below 9 I decided to stop the test. So what started out running almost 14psi ended up reading 9 or less within 10 mins.

Here's how I see the deal, if you set your regulator to 6psi. Then knowing after 10 mins. the pressure will drop almost 5psi.(and it does in the car OR not) then your going to have 1psi. left= engine about to quit.

I tested all three pumps this way and get the same test each time, I tried the same test installed in my car but with pressure regulator so I would no overcome the needles and got the same results but starting from 6psi. The darn pump cavitates after running awhile which makes the pump loose it's prime evidently and will never recover. Ok now that I have figured this out how do I FIX the problem??? I read where I need two regulators with my application but how can that effect or change the cavitation problem of the pumps when your sitting at an idle not consuming much fuel and flow is at a minimum? This deal with fuild flowing over and through fittings and getting distrubed and or causing vapor lock may be true if the pump was open and free flowing but when the fuel barely moves that idea im sorry is N/A.

I'll try the dual regs but can't see how that fixes a pump that won't even maintain PSI. sitting at idle speed or a quick run around the block in first gear.
This is BS, I should NOT have this problem to such an extent where the car will eventually run out of gas due to lack of fuel pressure having it set-up the way I have it, im not trying to demand all the power from the engine at this point, just a ride around the neigborhood after two weeks of this crap would be nice.
Pump is going into the trash!!! I'll buy something else with less hassel. Iv'e wasted the last day (14 of them)im going to on this headache.
I bought everything new because I didn't want troubles like this, certainly did not expect all of this from such a simple install and basic idea. One reg two reg, it should still work with either or as long as there's one and better with two im sure, but NOT at all just doesn't cut it for me!
Im ordering a pump with a return line, and installing two regs. Hopefully that should cure my problem and won't have to listen to the WA-WA-WA of the other pumps.
Sorry I vented on this subject, im sure this pump would work great on a race car with the pedal to the wall but for both worlds I believe the line return style pumps would probably be a better choice for me.
Thanks for all the replies and help on the subject/s


[This message has been edited by Gary (edited 12-17-2001).]

[This message has been edited by Gary (edited 12-17-2001).]

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TomP
Gearhead

Posts: 3609
From: Delta BC Canada
Registered: Dec 99

posted 12-17-2001 09:25 PM     Click Here to See the Profile for TomP   Click Here to Email TomP     Edit/Delete Message   Reply w/Quote
Gary

I think the return line system is a better idea in that it lets the pump flow freely, you need only enough pressure to keep the bowls full... even 2 or 3 psi will be fine, you can keep your system almost as is, just run the regulator off the end of the fuel log and a hose/tube from it's outlet back to the tank. I'd also say running a larger inlet into the pump and a bigger tank to pump line is a good idea. I use 5/8" hard line and -10 hose into the pump and 1/2" tube and -8 from pump to reg.

A problem i had was the fuel pump uses fuel to cool and lubricate it too, run it out of fuel even momentarily and it won't work right afterwards. In my case the georotor pump (mallory) would actually let the rotors expand and seize in the housing...pump would stop. It'd work fine after cooling down.

The Holley style pumps with moving vanes would gall the housing and having scratches would drop the pressure. I had problems with the regulators too. I have a way overkill Barry Grant pump and a Russell regulator now, it solved my problem, but probably wasn't the only way to have done it.

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Gary
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From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-18-2001 08:51 AM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Tried a tempoary test by connecting a return line off the side of the regulator that I wasn't using to the tank. In the line I added a valve to control the amount of flow. I just ran the line from the reg. back to the tank and just stuck the line into the filler cap opening to test. I just cracked open the valve abit just to keep the flow going through the pump but still maintaining 12psi. with reg. adusted at full flow. I then set the pressure to 6psi and started the car and re-adjusted the pressure abit and let it run for 20 mins.----Result: Steady pressure at the gauge and no cavitation at the pump
Test conclusions: All the pumps I guess were fine, they only needed fuel moving through them enough to keep them from cavitating and losing their prime. One would think as the engine is requiring fuel that would be enough to keep the flow going through the pump but maybe not at idle. Im no expert thats for sure but think for a street application a return line pump or return line regulator is the way to go and should make the pump last longer as it doesn't have to work as hard and keeps cooler fuel passing through the pump allowing the pump to run cooler
Cooler fuel is better that hot which is another plus side to better performance in any application.
Now I have to go out get a few parts, install them and see if it works... >fingers crossed<

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steve'66
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From: Sonoma,CA,USA
Registered: Mar 2000

posted 12-18-2001 11:00 AM     Click Here to See the Profile for steve'66   Click Here to Email steve'66     Edit/Delete Message   Reply w/Quote
Sounds Good Gary!

Hope it works out for you.


SteveW

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Ryan Wilke
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Posts: 607
From: Stanton, Michigan
Registered: Oct 2000

posted 12-18-2001 11:57 AM     Click Here to See the Profile for Ryan Wilke   Click Here to Email Ryan Wilke     Edit/Delete Message   Reply w/Quote
This was a good learning-curve thread, guys!!

Ryan

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Fordwiser
Journeyman

Posts: 85
From: Metamora, Illinois
Registered: Dec 2000

posted 12-18-2001 02:04 PM     Click Here to See the Profile for Fordwiser   Click Here to Email Fordwiser     Edit/Delete Message   Reply w/Quote
I wonder if you could shim the pressure relief valve in either the blue or black Holley pump and run a return style regulator with a return to the cell. The pump then wouldn't deadhead or cavitate, plus would run cool because of the free flow of fuel. Then you could use the pump/pumps you already have and not have to spend more money!
Roger

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Just Strokin
Gearhead

Posts: 179
From: Tuscaloosa, Alabama
Registered: Dec 2001

posted 12-18-2001 02:41 PM     Click Here to See the Profile for Just Strokin   Click Here to Email Just Strokin     Edit/Delete Message   Reply w/Quote
Just my 2 cents on your fuel tank being mounted backwards.....You will need to keep it almost full if you go drag racing or do a lot of cornering.....i doubt if you have pickup tubes in the tank to follow the fuel as it 'sloshes'.

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Gary
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From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-18-2001 03:00 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
Well you all won't agree with my idea but I installed a fitting to accept a very small brass valve at one of the outlets of the reg.
It is a 90 degree valve and has a 1/4" compression fitting pointing downward. I then ran 1/4" copper tubing from that all the way back to the tanks sump fitting that wasn't being used. I then got a fitting to tread into the sump that would also have a compression fitting for the 1/4" tubing. I ran the tubing into the sump and extended it to the back of the tank far away from the pump pick-up. Seems to work ok and can regulate the amount of fuel being returned back to the tank I only have to crack the valve abit to keep the pump from cavitating and believe it or not the pressure goes up slightly with valve opened some because it's not caviataing As long as you set and leave the valve at a certain setting the regulator adjustment works fine and seems to be accurate
Result: able to use my black pump after all and not having th cavitation problems as before.

BTW, cost for mod was 23.00 bucks! Alot cheaper than the cost of a return style reg. thats for sure and all the tubing and fittings. Also, Holley does not make a return style regulator...only return pumps.
Other wise your looking at using a Mallory reg. or other.

[This message has been edited by Gary (edited 12-18-2001).]

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n2oMike
Gearhead

Posts: 719
From: Spencer, WV
Registered: Jan 2001

posted 12-18-2001 03:43 PM     Click Here to See the Profile for n2oMike   Click Here to Email n2oMike     Edit/Delete Message   Reply w/Quote
It was mentioned earlier in the fuel pump post that the backwards sump is not a good idea. I shared my problems with a REAR mounted sump that was not deep enough. You might want to check it out.

Good Luck!

------------------
Mike Burch
66 mustang real street
302 4-speed 289 heads
10.63 @ 129.3
http://www.geocities.com/carbedstangs/cmml_mburch.html
http://www.fortunecity.com/silverstone/healey/367

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Gary
Gearhead

Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-18-2001 05:01 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
I forgot to mention, CS modifies stock type Holley regulators so they can be a return style regulator. The change they do is to convert one of the two outlets to a inlet and the other the return, the stock inlet is now used becomes the outlet. Price is around 65.00 and their number is: (636) 723-4996
they have them in stock.
In case you wanted to know

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Gary
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Posts: 677
From: Sarasota, Fla. USA
Registered: Jun 99

posted 12-18-2001 09:38 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
No2, the sump is 2-1/2" deep on my alum. cell and I angled the tank down abit in the front torwards the front of the car. the sump is pretty low and just above the bottom of the 9" rear. My tank is fairly tall @ 17.5 gallons so hope between those two things I'll be ok. For the street I think you brake more than hard accel so we will see how it works.
Also I have a foam filled tank so that will help too. When I designed this tank I should have put a baffled floor over the sump but I thought of it after they started building it.

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unklshu
Gearhead

Posts: 523
From: San Bernardino, Ca
Registered: Jul 2001

posted 12-19-2001 12:48 AM     Click Here to See the Profile for unklshu   Click Here to Email unklshu     Edit/Delete Message   Reply w/Quote
OK then Gary I have read this thread all the way through now and if I am correct the problem is solved?? What a great brian storm thread. but my question to you Gary is....Does she just HAUL A$$ like nobodies business??? Hope you enjoy the ride if the problem is solved. Man what would you do with out M&M??

------------------
joe
2001 SVT Cobra
68 GT Fastback
98 F-150
90 Escort GT (smokes the tires in all 5 gears, or just smokes through all gears)

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