Relocation or Second Pump?

[Jaguwire]

Got nervous after reading numerous posts about low fuel pressures. Hooked an A/C gauge to the port on the fuel filter. 8 psi at idle, 5 psi just revving the engine. Duct taped the gauges to the window and road tested with the PowerMax3 on 9. Fuel pressure dropped to almost 0 psi when the boost shot up over 30 psi. With DD2's and a Con OFE here in a box and an HX40 and Jardine exhaust in the works, I'm sure I need more fuel! Should I relocate the stock pump or add another pusher (e. g. Enterprise kit)?





________________



Jaguwire





2001 Quad Cab 4X4, Permatech liner and coated Westin bars, Powermax3 Adj. , Ceramic clutch disc (Grabby), PacBrake

 

[csutton7]

the worm can is opened again---some guys will tell you two pumps and others will tell you to relocate the pump--aftermarket or a new one from Cummins--



with two pumps if one fails the restriction caused by the dead pump will strain the vp44 possibly killing it also--how long will it take to kill the vp44 is unknown, but it won't do it any good that's for sure, but if you do some trick plumbing and wiring to circumvent the dead pump when it fails then you should be ok, but if they both die at the same time watch out(unlikely, but anything is possible)-----



personally I believe one pump relocated back by the tank is the way to go--Mallory has proven to last a year and the Summit pump has been installed on some trucks for 9-10 months now--the new Cummins pump is fairly new and has no longevity data yet---do some research and good luck..... chris

 

[Snow man]

SShaw,change your fuel filter,it may be plugged,bad lift pumps usually give erratic readings,as well as low. We put an FP guage on dad's truck,and got the same readings,changed the filter,ant they went to 12 pis idling,no less than 4 WOT. I put a booster pump inmone,but with your hp level,you might want to just move the stocker to the tank area,should be enough.

 

[Bigsaint]

At the very least move the Carter pump back by the tank and open up those restrictions with either modified banjo bolts or Weber fittings. The longevity of the pusher pump system seems to be above the single Mallory pump, IMHO. As Chris stated, if either pump does die, it will need to be replaced a. s. a. p. . As for the Mallory, I'm on my 3rd now ( first one lasted about 3 months, 2nd lasted almost 9 months). It's a great pump when it's working as the psi's are adjustable and the pump can be re-built. I'm not sure what will make it last for the long haul but I'm not ready to give up on it yet. For sure, more R+D is needed in this area. If you add a permanet FP gauge to your truck you will know when the pump is dying as they don't just quit without either loss of FP or erratic FP readings.



Scott W.

 

[csutton7]

Big Saint--gravity feed-I think is the next solution---chris

 

[Ramafid]

I bought a new 3990105 and moved it back to the tank area and havn't had a problem since. Pressure doesn't drop below 9psi unless it's real cold and then it goes to about 8psi. All is well after 7 mos.

 

[SEmerson]

I run a mallory. It did die alot sooner than I thought it would but it was only $10 for brushes. And a easy 10 min fix on the side of the road.

 

[JR2]

I moved my stock pump to the rear and added SS fule lines (removed all banjos on feed side). With all the boxes turned on I see 5 psi at wot and 10-13 at idle. It is my opnion that unless you are going for huge injectors and the hot boxes moving the stocker to the rear is fine. I also run a full time fuel press guage so I can watch what is going on.

 

[DSiemens]

Has anyone tried running 2 pumps in Parallel? I think all the discussions have been on running in Series in which a failed pump stops flow, but in parallel the only concern would be if the failed pump still flowed fuel.

 

[Bigsaint]

I agree Chris, sure won't hurt anything. As soon as spring comes, I just might drop the tank and add one of those bungs to the bottom.



Scott W.

 

[Mopar-muscle]

relocate to the rear .



11 months ,36k plus miles and the carter 4601HP is still ticking ...

 

[bigbrassmonkey]

dsiemens, the pumps are viened pumps, so you cant push through them

 

[jwhite1]

questions about supply pumps

Originally posted by csutton7

the worm can is opened again---some guys will tell you two pumps and others will tell you to relocate the pump--aftermarket or a new one from Cummins--



with two pumps if one fails the restriction caused by the dead pump will strain the vp44 possibly killing it also--how long will it take to kill the vp44 is unknown, but it won't do it any good that's for sure, but if you do some trick plumbing and wiring to circumvent the dead pump when it fails then you should be ok, but if they both die at the same time watch out(unlikely, but anything is possible)-----



personally I believe one pump relocated back by the tank is the way to go--Mallory has proven to last a year and the Summit pump has been installed on some trucks for 9-10 months now--the new Cummins pump is fairly new and has no longevity data yet---do some research and good luck..... chris

 

[jwhite1]

questions about supply pumps

There certainly is a lot of discussion about supply pumps on these 24 valve engines, and it seems to be uncertainty about what to do, if anything that will help this bucking problem. I had the opportunity to talk to Cummins the other day to discuss this problem with them. By the way, the gentleman I talked to was very nice and tried to be helpful. What he told me is that this is a common problem and to his knowledge it is caused by mixed signals from the ECM and not by supply pumps. He also said that the supply pumps have been pretty reliable, with only a few exceptions. The problem with putting two pumps in series with each other is that you will run the risk of 1 engine will not start, and 2 and worst of all, if transfer pressure gets too high, you may cause head seizure in the vp44, and that is something none of us want. I also asked about fuel treatments, and while he didn't discourage it he said the VP44 didn't have to have the extra lubericity. My 2001 24 valve 5 speed has the same problem everyone else has. It has a Power Puck on it -same with or without it on. I tend to agree we are getting mixed signals from the engine computers, but thats my thoughts. J White