Electric fuel pump plumbing

[gerg 10,871]

They do have a tendency to seize if rusty or have bits of crap in them

[Crazy2287 1,886]

Gerg Nailed this. Solid state fuel pumps do not need a return.

[Ando81 2,949]

Ok lads, thanks for clearing this up and saving me the time changing it, great work.

[Clevo120Y 815]

Do you still need a fuel pump hole blanking plate? I can send one with your manifold if you want.

[Ando81 2,949]

No thanks mate, the one I made up is not leaking anymore and I found a proper blanking plate off an efi block in my shed. Thanks anyway.

[XFChris 126]

So after a bit of playing around I am having a struggle with my goss electric fuel pump setup. I was driving along the other day and car started surging on petrol but was fine soon as I went back to gas. I turned the fuel pump on at home when I got home and once it pressurised in the carby, the pump stopped pumping. Is this normal? I pulled off the outlet from the pump and it filled a 2 litre bottle very quickly so I don't think it's a pump or filter problem, I have swapped the screw in solenoid on the side of the carby to see if that helps but still not wanting to run properly. I'm wondering if the pump needs to be able to return to the tank instead of cutting out when it pressurises in the carby. It seems strange because sometimes I can cruise along fine on petrol without any trouble and other times it only runs for a minute of so and dies.

 

Are you running one of these?

http://www.goss.com.au/attachments/Product/4361/ge242.jpg?ts=1362349430

 

 

I run one of a similar design. A couple months ago, i noticed that it does sometimes surge when I give it a bootful on petrol, others could be right about crap getting into the pump. I only have the pre filter that came with it. I'll add in a ryco fuel filter closer to the hard line, and see if that helps. probably wouldn't hurt for you to do that also.

[Ando81 2,949]

I've got exactly that pump mate minus the filter, my filter is just a universal low pressure filter that goes before the pump. It seems to get plenty of fuel when I flow tested the pump so I might have to rip the top off the carb and check for crap in there.

[Crazy2287 1,886]

Those pumps have really good lift, will easily pull fuel through the filter so it's best to mount the filter before the pump. hardline>filter>pump>carby

[Ando81 2,949]

Thanks for the help fellas, my fuel pump is pumping fine but I found the smallest piece of crap in the carby needle today. Pulled the jets and venturies out and they were spotless but a piece of crap the size of a piece of glitter was hiding in the needle & seat so carb was prob flooding causing it to run like crap. Went for a test drive, thrashing it on petrol and it seems to be fine now

[Ando81 2,949]

Just a quick question lads, when a clatter style pump gets to pressure does it turn itself off and restart as soon as the pressure drops or does it somehow relieve the pressure in the pump but continue to run. My ute is giving me grief again, once it primes the carby bowl it seems to stop pumping and the motor dies, run it on gas for a couple of minutes and can switch the pump back on again with success but only until it pressurises the carby again, about 35seconds on the highway. Before I spend another fifty on a new pump I just want to confirm that the pump is to blame.

[gerg 10,871]

The internal plunger is what does the pumping. It is energised by the solenoid windings which constantly cycle on and off by the simple electronics inside the body. The pulsing is always there as long as you have power going in. When the pump gets up to pressure, all that happens is the plunger cant pump any more so doesn't move until demand for more fuel lets it move again. If it's stopping after getting up to pressure, I'd say the plunger is in its idle position and getting stuck there, but when it finally decides to start moving, it's freed itself up and doesn't seize until it reaches pressure again. I reckon a new pump is on the cards.

[Ando81 2,949]

Thanks mate, I can turn the key on and off once the carby has emptied but the pump still stays in idle mode, must take a while to free up again and start pumping. Best try a new pump grrrrrr

[Ando81 2,949]

Thanks for all the help lads, a new pump fixed it straight away. Have put a full tank through it now and hasn't looked like surging. Winners are grinners

[Mustardxf2 310]

Bringing this thread up from the dead, lol

Now I'm piecing together my fuel system and I'm stuck on the check valves, now on summit and aeroflow they advertise check valves that release at 3psi. Is 3psi to low?

Now at idle where the pressure will build up it makes sense to release at a low psi as the carb is not needing all that fuel flow anyway.

under acceleration and WOT will the fuel still want to flow out the checkvalve or bypass it as its using more fuel then when at idle?

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[ando76 4,354]

3 psi is way to low. You need relief pressure above your reg pressure. Otherwise it will always be going over the relief and flow potential to the carb would be reduced to a dangerous level.  

If your interested in a properly designed and extensively tested fuel system, send me a PM. 

[Mustardxf2 310]

Pm'd

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[slydog 7,873]

Not a fan of the by passed fuel systems. I ended up with stammer or shudder in the lines. Only fix was BIG Mallory return reg bay mounted and larger return line than feed line. Just like in other fast cars LOL.

Starting with a quality pump like Aeromotive unit helps. I use a SS unit with a big Mallory return reg to trim and a Aeroflow non return to cut PSI pre-fuel log. Cos my carbs only need 2.5 PSI but need bulk volume a OS pump was the safest and best option in this case. 

[Mustardxf2 310]

So the idea of a return reg is the same as a check valve? Reliefs the line once pressure builds up to a set psi? And the normal reg is to set the psi to the carby?

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[slydog 7,873]

Return reg gives you options a check valve can't and allows for expansion within the single unit. Ill run the nitrous solinoides off the return reg as its a 4 port and the pump has heaps of head room. But if you need to adjust amount returned you wind in or out. Not as cheap as a by pass though.

My car runs webbers and needs more control to a lower level. I trim to 7.5 psi on the return reg and cut to 2.5 on the dead head carb feed reg. Yet when its mobile the nitrous will use 5.5 psi and all off the same fuel system and single pump thanks to the adjustable control.

[Mustardxf2 310]

And the return reg is it plumbed in before the carb after the dead head reg?

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[slydog 7,873]

No...Return reg is firewall mounted in the bay and BEFORE cut reg.Has return off 1 port and feeds dead head/cut reg. Dead head reg then has a fuel log off it and 3x -6 feeds to carburetors. By this stage the fuel has only has to travel maybe 500mm from cut reg to carbs.

Yes it takes 2 regs to make this work which cost money but it's also is more reliable in my application and needed due the amount of pressure drop I need while retaining volume of fuel.You can do it other ways im sure but this way has worked and did Drag Challenge,Summernats,PCM and Powerfest and so plus many many road km's with zero issues. 

[ando76 4,354]

The only issue I have with return regs when used in a normal carb situation is that it relies on the needles and seats inside the carb to hold the fuel pressure, which with big pumps like the aeromotive and even Holley black style pumps can be up to 14psi and a lot of volume. 

Yes the diaphragm inside the return reg is set to the desired pressure and the needle and seat should not see such a high pressure BUT, and it's a big BUT, if the diaphragm fails or can't cope with the volume then you are left with the needle and seat taking all the pump pressure and volume.  How is this so? Because with a return reg the main supply from the pump is a common port with the carb supply.  In common man speak they are basically one continuous line. It relies solely on the diaphragm and spring to relieve excess pressure and flow. 

Ankther downside is the extra line required to run a return reg.  basically your doing another whole length of the vehicle in line which adds extra expense and weight to the car. 

In my opinion a regulator should be left to regulate, nothing more.  It's a big job, especially when way to much pump is used. The beauty of the relief set up is that even if the reg fails, the carb will only ever see 9psi. And they can survive on that and get you home. 

My set up is identical to that used by Barry Grant, Magnafuel etc etc.  so people who really know what they are doing with fuel systems. It's just a cheaper, simpler version and I developed it with Allan as most people already have a Holley blue type pump so it can be retrofitted to it.  With the appropriately sized pump they work perfectly.  

[slydog 7,873]

Yeah it didn't work on mine.Killed regs every 6-12mths. Even tried a equivalent Magna fuel pump and it suffered stammer and as said before due to the pressure drop needed for the induction on the car I believe. But the current Aeromotive pump and combo of regs got it sorted and has been as such ever since. 

Yes it cost more in the end cos I had to basically replace the system and try various pumps where If I fitted the Aeromotive and combo of regs to start with I would of saved money LOL. Arrrrgggggggh.

 

[ando76 4,354]

Agreed. The webers desire for 3-4psi but still bulk volume makes it an interesting system, at your performance level.

I'll see if I can get tapatalk to work and post the video of the fuel going over the bypass on Dickies race car. 

[ando76 4,354]