??'s about a pusher set up

[Bill_L]

So I was sitting here searching around the web for fuel pump and trying to find pumps that might last. I started to wonder about a possible set up that might make it so that the pump(s) don't work as hard.



It seems to me that the Carter pumps are doing alright so what I thinking of is take the fuel line from the take put in a Y run each side to a Carter pump and then out of the pumps run into another Y to push them back together and either back to the stock line of a all new line to the lift pump. The thinking is that with both pumps running neight of them would have to work as hard and you might even be able to adjust down the voltage to the pumps if you wire it right.



If the pumps are not running at max all the time they should last long right?

I got this idea from a complete fuel system that had for my Mustang at one point.



Any comments, ideas, opinions?



Bill

 

[Jetson]

I don't know if they would last longer, but I think this would be a better setup than 2 pumps on one fuel line like most people are doing with their pusher pumps. If one pump goes out in the single line setup, the fuel psi drops drastically. With a Y in the line, a pump could die and the other could take up the slack. I would try to pick lower GPH pumps and try to set the pressure at 10-12 psi so the 2 pumps don't completely swamp the VP 44. OR, I would run a switch to the pumps so I could run one at a time and then you could run the higher volume pumps and not have to worry about being stranded.

 

[EricBu12]

I made a 7 psi pusher inline back by the tank and I did a bypass with a one way check valve so that if the pusher died, the lift can draw the fuel through the bypass from the tank. I also replaced the stock lift pump with a carter 15 pound pump. the pusher is also a carter # 4600 7 psi and 100 gph.



I see 13 psi at idle

10-12 cruise

and no less than 8 at WOT



I also put a 30 micron filter before the pusher to take out any crap in the system

Filter also has a Water in fuel sensor and a separate fuel heater



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[me4osu]

EricBU12

How much did that system cost? And where did you buy the parts?



Jetson

That is a good idea with the manifolded system with a switch; I might do that when I put my pusher pump in. One thing I would add is that, in order for one pump to take up the slack for the other, when the suction and discharges are manifolded, the discharge port of each pump needs to have its own check valve.



I have not taken a bad lift pump apart, but I believe that when they go bad, is when they lose their vane-to-case seal. This causes them to lose their positive displacement rendering them unable move fuel from suction to discharge. By the same token, if there were a healthy pump manifolded parallel to the failed pump, it would tend to re-cycle (backflow) through the failed pump. A check valve at the discharge of each pump would stop the re-cycling and enable the healthy pump to take over properly.

 

[DEZLPWR]

EricBU12...

Your fuel pressure #'s seem low for the set-up that you are using... I was seeing better readings than that with just my stock lift pump by itself in the stock location with the Comp Box! Now I have a stock lift pump and the same 7 psi Carter pusher that you have back by the tank, and I see 23-24 psi @ idle and no less than 20 psi @ WOT with the Comp on 5-5.....

Do you have some sort of regulator on yours to reduce the psi, or does your fuel filter set-up reduce the psi?

 

[Jetson]

I don't think you want high psi. You will be recirculating a lot of fuel, heating it up and possibly causing some foaming. Around 10 psi is moving plenty fuel without overdoing it.

Very nice setup Eric!

 

[DEZLPWR]

My fuel pressure is probably overkill, but I don't think I am causing harm to my fuel system... . I would rather have high fuel pressure vs. low fuel pressure. Plus, there are several members out there with thousands of trouble-free miles running the same psi's that I am running. I think Steve St. Laurent has the same set-up as I do, and he has close to 50,000mi on his fuel system if I am not mistaken... .

Steve, do you want to chime in here? In my previous post, I was just trying to figure out how EricBU12 could have virtually the same set-up as me, yet have much less fuel psi.

 

[Todd T]

DEZL



its been rumored that anything higher than 20PSI or so can cause a seal failure in the front of the VP44. washing down the engine oil.



I havent witnessed it yet, just heard the rumor



remember pressure=resistance.



it is safe to say that as long as you have a positive pressure AT THE PUMP, at all times, you are OK. what that pressure amounts to is your call



Eric, 8PSI at WOT is fine in my book. and i had enough power to slip that OFE, DEZL has in there

 

[Steve St.Laurent]

I agree that Eric's fuel pressures are lower than what I've heard from other people running the 7 psi pusher to a 15 psi pump at the engine - why I don't know. His pressures are certainly good enough. As far as the seal blowing on the VP44 I know of two vendors that ran tests with up to 60 psi and didn't have any seals blow. One of them tested at those kind of pressures for over a half hour on a load dyno.



I feel like a broken record any more on the pusher pump thing but I'll say it again - when I installed the pusher pump on my truck I talked to a Cummins engineer and a D/C engineer that is responsible for the ISB in our trucks - BOTH of them said the higher the pressure the better up to a point and that ~20 psi would be NO PROBLEM. The only issue they said you could run into with fuel pressure higher than 7 psi is a possible hard to start condition - that's the reason for the lower duty cycle on the stock pump while cranking. I've probably posted that at least 30 times in the last year or so. Thus far there have been no reports at all of any damage to the VP44 running around 20-22 psi - nor has anyone reported having a VP44 go bad with a dual lift pump setup.

 

[DEZLPWR]

Thanks Steve....

Now I can rest better @ night... . hehehe Oo. Oo.

 

[KatDiesel]

I just added a Carter 4600 pusher.



Idle is 21 to 22psi



WOT BD IV's + COMP 5x5 = 10 psi



Pump makes a lil noise, but its livable. Also used braided steel lines and fittings, so if my pusher dies, I simple slap in a male to male fitting and go right past it. Same on the OEM pump, if it dies, I use the fitting to join the fuel lines.



I just don't have a permenet fuel pressure gauge..... yet.

 

[EricBu12]

Well at least I have some pressure and it won't go down to 0 without me knowing it.

One thing though, I have an electric fuel pressure sendere and it 0's out when the key is on and no pump running and then when the pump runs, it peggs 15 psi then when running, it is 13 at idle. I think it is doing great.



With all the parts, I spent about $500 I bought the jannetty racing kits for the carter pumps and the racor filter is a top quality unit. I think it might be restricting a little PSI's but that is a small price to keep the pumps clean. there is an LED warning for the water sensor and the filter minder (restriction) that is in a guage on the dash. Had to route a Wire loom along the frame cause of the 4 wires to go to the unit.



I will be towing a rental trailer for may madness and I am confident all will be well but I do have a replacement element for the racor filter just in case...

Thanks for the compliments everyone, I did this from another member RAddodgeRADdodge

and he has a longbed so it fit on the frame rail.