Fuel pump runs, but no fuel pressure?

[horizontalkev]

Rewired walboro 255 fuel pump and Aeromotive fpr and aftermarket fuel lines.

When did this happen? Car was running strong, shut off motor and 10 minutes later started it up again, sputtered and slowly died. Cranks over, but no start afterwards.

What have I tried? Bought a new relay, fuel pump fuse is okay and I've turned on the fuel pump manually and it ran. I can also hear it running while trying to start the car.. I am not showing any fuel pressure and not getting fuel to the fuel rail.

I have half a quarter of fuel left. What the heck is wrong?

 

[n0de]

Darn, WES I just tried to contact DSM Rookie but i believe he has some privacy setting on which prevents this. I would like to know what the measurements are of that bulkhead on the side where it sleeves over the fuel pump nozzle.

 

[WES_393]

They likely clamped the upper part of the hose onto the fitting before install, then slapped on the epoxy to seal the hanger. So you could just remove the fuel pump and chisel the epoxy off to remove the fitting and hose.

In the pic I posted, the pump outlet just slides into the fitting. It seals using a plastic spacer and rubber O-rings, like this:
(Left is fuel pump. Ignore the object on the right)

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Darn, WES I just tried to contact DSM Rookie but i believe he has some privacy setting on which prevents this. I would like to know what the measurements are of that bulkhead on the side where it sleeves over the fuel pump nozzle.

It looks like a standard 90° bulkhead fitting (like below) that's been bored out. But I'm positive you could find a similar/better fitting with a quick search on Jegs or Summit.

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[SICK SOCIETY DSM90]

Looking at your fuel pump the micro filter for your pump looks to be in bad shape could be clogging up there also. I had an 99 explorer that bucked and then eventually had same problem as yours did so I thought the pump must have been going bad changed that filter and the inline fuel filter and works like a champ. Your on the right track with the sending unit also has to be sealed to get pressures to build up in tank the system needs to be sealed no leaks or your pump will have hard time keeping pressures that you need. Keep updated

I forgot have you cleaned the tank out before re installing the pump. I always clean the tank when putting new fuel pumps in or anytime I open it up since contaminants can get into the tank when doing installs or get rid of bad gas.

 

[Colt4G63 also]

I had a 255 clog up on me before, and the symptom was difficult primes on a dry pump, and when it got bad enough, I was actually losing fuel pressure when under boost. Luckily I was able to save my pump: I removed the pump, and made a funnel by wrapping a sheet of paper around the outlet of the pump. I then used a small zip tie to hold the funnel tightly to the end of the pump. Then I plugged wires into the pump, hooked up to a battery via a push button, with the polarity reversed. (The pump will pump backward with reversed polarity.) Then fill the funnel with fuel, and reach down through the funnel with a CLEAN set of hemostats, or tiny needle nose pliers. Grab the little pin in the anti drain back valve, pull it up gently, and push the button so the pump runs in reverse. Repeat this with a few funnels full of clean fuel, and then reinstall the pump with a new pickup strainer.

 

[horizontalkev]

They likely clamped the upper part of the hose onto the fitting before install, then slapped on the epoxy to seal the hanger. So you could just remove the fuel pump and chisel the epoxy off to remove the fitting and hose.

In the pic I posted, the pump outlet just slides into the fitting. It seals using a plastic spacer and rubber O-rings, like this:
(Left is fuel pump. Ignore the object on the right

It looks like a standard 90° bulkhead fitting (like below) that's been bored out. But I'm positive you could find a similar/better fitting with a quick search on Jegs or Summit.

Oh yeah that makes sense, I hope the epoxy doesn't give me a problem when cleaning it off. Very good information thank you, I'll have to search for the exact sizes, or are all bulkhead fittings pretty universal? And from the picture it doesn't look like any welding was performed is there some type of crushable washer used?

Looking at your fuel pump the micro filter for your pump looks to be in bad shape could be clogging up there also. I had an 99 explorer that bucked and then eventually had same problem as yours did so I thought the pump must have been going bad changed that filter and the inline fuel filter and works like a champ. Your on the right track with the sending unit also has to be sealed to get pressures to build up in tank the system needs to be sealed no leaks or your pump will have hard time keeping pressures that you need. Keep updated

I forgot have you cleaned the tank out before re installing the pump. I always clean the tank when putting new fuel pumps in or anytime I open it up since contaminants can get into the tank when doing installs or get rid of bad gas.

And yeah there was quite a but of gunk in my tank that I cleaned, I'm sure I'm up for a new fuel filter aswell. I will keep you updated, I've been working all day so I won't get a chance to mess with things till tomorrow morning.

I had a 255 clog up on me before, and the symptom was difficult primes on a dry pump, and when it got bad enough, I was actually losing fuel pressure when under boost. Luckily I was able to save my pump: I removed the pump, and made a funnel by wrapping a sheet of paper around the outlet of the pump. I then used a small zip tie to hold the funnel tightly to the end of the pump. Then I plugged wires into the pump, hooked up to a battery via a push button, with the polarity reversed. (The pump will pump backward with reversed polarity.) Then fill the funnel with fuel, and reach down through the funnel with a CLEAN set of hemostats, or tiny needle nose pliers. Grab the little pin in the anti drain back valve, pull it up gently, and push the button so the pump runs in reverse. Repeat this with a few funnels full of clean fuel, and then reinstall the pump with a new pickup strainer.

So instead of the normal positive to positive and negative to negative, I do positive to negative and negative to positive? This won't mess anything up right? What if I used Seafoam instead to help clean?

 

[c2ypt1c]

I would replace the epoxy and fitting with a proper bulk head setup like this:

Nice!! Instead of buying that damn 14mm inverted flare to 6an fitting for the rediculous price of $30, I might as well do this

Darn, WES I just tried to contact DSM Rookie but i believe he has some privacy setting on which prevents this. I would like to know what the measurements are of that bulkhead on the side where it sleeves over the fuel pump nozzle.

He said he used 8an and drilled it to accept the pump, but it looks like he cut off the tip (a result from drilling?). Also, looks like he goes from 8an to 6an. This is how I'd do it:

http://www.summitracing.com/parts/fra-483308/overview/
http://www.summitracing.com/parts/sum-220839/overview/
http://www.summitracing.com/parts/fra-497208/overview/
http://www.summitracing.com/parts/sum-220690/overview/

 

[horizontalkev]

Those 4 things from summitracing are all I need for for my fuel pump? Im assuming I have 6AN fittings right? And how exactly will that be secured and sealed to ensure it's leak proof? Also another thing, my positive and negative wires for the pump are ran through another drilled hole in the sending unit how can I redo that without using epoxy and risking them shorting out?

 

[c2ypt1c]

Those 4 things from summitracing are all I need for for my fuel pump? Im assuming I have 6AN fittings right?

No, you'll have to upgrade the entire feed line to the rail. This includes 6an hose + hose ends, 6an fuel filter, and 6an rail adapter.

Unless there is some adapter to fit the stock fuel line to 6an. Actually, come to think of it, you could cut the rubber line that comes right off of the sending unit and use a 6an barbed fitting:
http://www.summitracing.com/parts/sum-220701/overview/
So instead of buying the last hose end from the four links that I previously posted, you would buy this one.

This should work just fine but I'm not 100% sure if that factory rubber hose is 6an (or close enough). Anyone else know for sure?

And how exactly will that be secured and sealed to ensure it's leak proof?

AN fittings taper into the hose which creates a very tight seal. For the barbed fitting, you'd just need a standard hose clamp and make sure it's tight!

 

[horizontalkev]

It's all upgraded I just don't know if im using 6an fittings

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What I meant about being sealed is the part that goes through the sending unit

 

[c2ypt1c]

It's all upgraded I just don't know if im using 6an fittings

EDIT: just use a wrench on the fitting. 6an = 11/16 wrench. 8an = 7/8 wrench

What I meant about being sealed is the part that goes through the sending unit

The nut and bulkhead should provide a seal, but just to be safe you could use an o-ring to help seal it up:
http://www.summitracing.com/parts/vta-33858-vuf/overview/

 

[horizontalkev]

Ah, I see. You can measure the outside diameter of your hoses. In the product description, summit gives specs for their hoses, to give you an idea. Here's 6 and 8an:
http://www.summitracing.com/parts/sum-230620/overview/
http://www.summitracing.com/parts/sum-230820/overview/

.547 and .641 inches, respectively.



The nut and bulkhead should provide a seal, but just to be safe, you could use an o-ring on both sides to help seal it up:
http://www.summitracing.com/parts/vta-33858-vuf/overview/

Thanks man you've been a lot of help. I will figure out if I have 6 or 8 AN and then refer to your links for the parts thanks.. And that's all I'll need right?

 

[c2ypt1c]

Thanks man you've been a lot of help. I will figure out if I have 6 or 8 AN and then refer to your links for the parts thanks.. And that's all I'll need right?

Read my edit, much easier. But yeah that should be all you need.

Also, that o-ring might dissolve in e85, so you might want to put it on the outside of the sending unit. Just a heads up...

 

[horizontalkev]

Oh yeah that will make it much easier to find out thanks man. And unfortunately I no longer have e85 fuel around here.. They changed it last month to diesel. I may go for avgas

 

[horizontalkev]

After yesting the fuel pump (and gettind getting feel all over myself) i then decided my fuel pump is OK so I looked elsewhere and Found the problem... Fuel filter is clogged. The fuel that came out of it was a milky white, is that bad? Can I somehow clean this fuel filter or replace just the inside, or will I have to buy the whole thing? SX performance model 41002.. now I shall go take a shower

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[c2ypt1c]

6an right?
http://www.summitracing.com/parts/rus-650133/overview/

 

[horizontalkev]

6an right?
http://www.summitracing.com/parts/rus-650133/overview/

Somebody once told me 6AN, so I'm pretty sure that's it.. I forgot to check the sizes. I looked up the filters model number and it said 10AN fittings, that can't be right.. Can it?

and is that fuel filter a good one? It is cheap.. thanks for your help man

 

[c2ypt1c]

Somebody once told me 6AN, so I'm pretty sure that's it.. I forgot to check the sizes. I looked up the filters model number and it said 10AN fittings, that can't be right.. Can it?

10an would be stupidly huge...

and is that fuel filter a good one? It is cheap..

40 micron, ss filter element, 492lph 1000+hp capable...yeah it's good.

STM sells them as well, in case you're scared of summit for some odd reason or want to support a vender:
http://www.streettunedmotorsports.com/parts/russell_fuel_filter_650133.htm

 

[horizontalkev]

10an would be stupidly huge...



40 micron, ss filter element, 492lph 1000+hp capable...yeah it's good.

Haha that's what I thought. And the lines sure as hell don't look that big either. I'll try out wrench sizes tomorrow morning and see what I come up with. I'm almost willing to bet 6 An though. And thanks for your help, with the links and advice. DsmTuners need more people like you

One more thing before I forget, I have never seen milky gas pour out of a filter before like it did tonight.. Is that water? Or maybe the fuel pump sock disintegrating?

 

[c2ypt1c]

thanks for your help, with the links and advice. DsmTuners need more people like you

No problem man, glad I could help

Let us know how it goes...

One more thing before I forget, I have never seen milky gas pour out of a filter before like it did tonight.. Is that water? Or maybe the fuel pump sock disintegrating?

if the filter is paper element, perhaps it's breaking down? That would be my first guess.

 

[horizontalkev]

No problem man, glad I could help

Let us know how it goes...

I'm ordering that fuel filter tomorrow once I verify fitting sizes. I will keep you updated

 

[horizontalkev]

So neither 11/16 or 7/8 even fit the fittings.. Either I'm doing something wrong or these lines are meant for some unrealistic application. The lines say earl on them.

 

[c2ypt1c]

So neither 11/16 or 7/8 even fit the fittings.. Either I'm doing something wrong or these lines are meant for some unrealistic application. The lines say earl on them.

What size wrench fits it? Maybe it really is 10an WTF

1" = 10an fitting

If it is, I'm interested to know how the line is adapted to the rail...epoxy'd a 10an fitting to it? Is the rail aftermarket?

 

[horizontalkev]

What size wrench fits it? Maybe it really is 10an WTF

1" = 10an fitting

If it is, I'm interested to know how the line is adapted to the rail...epoxy'd a 10an fitting to it? Is the rail aftermarket?

I tried the two sizes and had to leave for work so I didn't try any other sizes, will tonight though.

And I sure as hell hope it wasn't epoxy'd on, although it wouldn't be surprise me if it were.. Everyday I find something new about this car that makes me wonder about what the previous owner was thinking . It's an AEM fuel rail

 

[Diamond Star Werks]

What size wrench fits it? Maybe it really is 10an WTF

1" = 10an fitting

If it is, I'm interested to know how the line is adapted to the rail...epoxy'd a 10an fitting to it? Is the rail aftermarket?

-10an equals 10/16" -12 is 3/4"~12/16
each -an is 1/16th of an inch.

 

[horizontalkev]

-10an equals 10/16" -12 is 3/4"~12/16
each -an is 1/16th of an inch.

So 8AN=1/2 while 6AN= 3/8?