Lift Pump Problem maybe about to be solved

[hammersley]

Check out this link at the Diesel Page - can we get in on this?????



http://forum.62-65-dieselpage.com/ubb/ultimatebb.php?ubb=get_topic&f=3&t=002680

 

[Amianthus]

Ummm, what exactly would you like to get in on?

 

[JR2]

I would be interested in more info about the in-tank pump the guy was talking about... .

 

[EShaw]

Amianthus,

Sounds like you've been busy... ... ... . I know the fix is out there. It takes guys that can think out of the box to cure this..... please keep us in the loop... ... ... Great Job!

Highest Regards,

Eric Shaw

 

[Amianthus]

Whoa!

I'm not doing anything that someone else hasn't done on here before. Those guys are looking for an in tank pump. If they succeed, great. But when it fails, oy!

I'm running a summit pump now that's frame rail mounted. The frame rail mounting seem to be the best way to go for maintenance. Lots of other guys have gone this route before me. I'm just following thier lead.



I thought that the Dmax guys could benefit from this same information because in thier design they don't have a lift pump at all. The HP pump has an integral LP pump (same as our VP-44) and is tasked with doing the whole job. Sucking fuel from the tank, through the filter, and various plumbing, and pushing it into the HP pump. They could be in a worse situation than we are when it comes to this low pressure fuel pump situation. Some are losing prime frequently, stalling, and on and on. I just thought that they could use the information that others on this board have generated.

 

[Whitmore]

Great idea

I have thought all along that a pump in tank combo would be the cats meow, it has worked succesfully for years in other applications. We do need to match what is in place now and that is 60 gph and 15 psi... ... ... . JMO... ... ... ... ... . Kevin

 

[Bill_L]

Why hasn't anyone released any kind of intake pump kit? Is there a problem with the pumps being in the diesel fuel?



I would think that this should almost be a factory set up like it is on any gasser just with a lower pressure pump.

 

[CannonBall]

Kevin, the 60 GPH at 15 PSI rating you are speaking of is the best the factory pump can do maybe at idle. The minute that more fuel is required those readings can do nothing but drop off. When fueling mods are performed the numbers get even worse. There is a cure for this, it's called a regulator with a higher volume/pressure pump.



I just installed a frame mounted, inline pump with a small inline 10 micron filter behind it. The pump is a Holley but I am told it is made by Walbro. Walbro makes world class intank fuel pumps. This pump can be regulated to 50 GPH at 15 PSI. Just ahead of the pump about 12 inches I mounted an Aeromotive fuel regulator.



I set the regulator so the gauge reads 16. 5 PSI. The regulator maintains this pressure at idle as well as wide open throttle. I do look to get pictures up soon.



As far as mounting a pump in the tank, that should not be a problem. We had M-series trucks with multi fuel engines that had in tank mounted transfer pumps.

 

[Whitmore]

Cannonball, I understand what you say comlpletly and do agree with you ,I would like to see 60 gph and 15 psi all the time at the inlet to the vp-44, any more than this and you take a chance of washout and any less than this you jeprodise the lubricity and cooling to the vp-44, so I agree that a higher psi pump is key but I have a hard time on the volumn issue,

The bibbest problem right now with the frame mounted pump is the fact that it must pull a vacuumn as there is a negative head feed to the pump, There is a solution for that too and it is to make a new feed from the bottom of the tank to the lift pump, I do think that 95 % of the lift pump failures would not exist if it were set up this way and with the pump being mounted back by the tank. The other fix would be to do the in-tank pump set up which would be the same concept in the end.

I do not think that the OEM pump is all that faulty but do think the problem lies soley in the fact of vacuumn and no head pressure... ... ... ... ... ... Jmo... ... ... ... ..... Kevin

 

[EShaw]

Whitmore,

The DOT frowns upon gravity feed... ... ..... otherwise we wouldn't have this problem at all... ...

Eric

 

[CannonBall]

Kevin, I mounted my inline pump at the bottom portion of the frame. It can gravity feed here. I am not planning on letting my fuel level drop much below 1/4 of a tank.



If this set up does not last then I will mount a Walbro pump in the tank.



This lift pump situation is real and needs to be addressed. The location of the factory pump is terrible. The factory Carter pump is far from stellar. The last thing the VP44 needs is lack of fuel pressure.

 

[csutton7]

Cannonball--is your pump truly gravity fed??? I thought you used the OEM feed from the tank to supply the pump--if you did it's not gravity fed--it still needs to suck fuel up and out of the tank, but when the fuel reaches the apex then you will get the gravity effect, not much gravity though---one question does the line from tank to pump stay primed--I'm don't know if it does, but if it does then then that will surely help---one other thing I had placed a regulator where you have one and my BG220hr pump didn't last two months--so keep an eye on it--others have had better luck--and maybe my downfall was line size because I increased it to -8AN from tank all the way to the VP44... I am now 100% gravity fed out of the bottom of the tank for 10 months now and all the parts are holding up---knock on wood-----an IN-TANK pump would be the simple answer, but I couldn't find one---that doesn't mean it's not out there---may have to get one off of an old military truck and see if it can be adapted or just keep on looking----the saga continues-----chris

 

[jtisdale]

Amianthus-

Boy, am I glad you live within hauling distance from me!

 

[DAWG-1]

Solved......

I made a fuel system with all -6an line, a pusher pump, an inline fuel filter (sintered bronze), a relay with wire. I have 22 psi at idle.

If you would like me to make any of you a kit just let me know. E-mail me at -- email address removed -- . Sam

 

[Amianthus]

Fixed it.

I now have it fixed. I have completely disconnected the stock pump and am only using the new pusher pump. I am now getting ~16 psi at idle (post filter) and ~10-12 psi WOT (with box). No stumbles or misses. I have the jumper wire for the new carter in my tool box and have the ports plugged with a spare hose so that just in case the Summit pump dies, I can disconnect it, and re-connect the stock pump to get home. Should be able to make the switch in under 30 mins. if need be (hopefully not).



You don't want more than 20 psi at any time. There is a seal on the VP-44 that can fail at higher pressures and will fill your crankcase with fuel. That's bad.



Yes, gravity feeding will work. The siphon effect will keep a pump on the frame rail full of fuel. Trust me on this. You don't want to be taking baths in #2 oil. There's a trick I did to get it to stop, and you have to re-prime the system when you are done. Yes, it will work. Any other questions?

 

[jtisdale]

Just one...

When are "we" doing mine?

 

[Amianthus]

As soon as YOUR wife says it's okay.

 

[jtisdale]

She is getting better though, she even helped me take the muffler off!:--)

 

[CannonBall]

CSutton, I now have size -06 Russell Twist Lok Hose running from the fuel tank all the way to the inlet on the VP44. There is no OEM line on the supply side anywhere.



As far as gravity? There is plenty. Every pair of coveralls I own are now thoroughly diesel soaked. I made the mistake of upgrading my fuel lines with a full tank of fuel, plenty of gravity feed. I had to blow a little air back the line to get the flow to stop.



As stated earlier, I am not going to let the fuel level drop to much below 1/4 of a tank. As long as the fuel level is above the level at which the inline lift pump is mounted the line will stay primed. The pump I am using is self priming as well.



You did mention that you experienced problems with the location of the regulator. What failed for you? The pump or the regulator? Regards. Gordon.