Well, youre probably right there rattle,

I actually had a pretty new oem pump in mine, but its true, that it doesnt make sense (for an informed person) to wait for the lift pump to fail before installing a pusher pump of any kind. Most of us already know that once driven with 0 pressure, the damage has already started, and may be done.

That is why the info is posted, so people can plan ahead, and solve a problem before it happens. This is an opportunity to install a seperate pump back by the tank (any brand they prefer), and with thought, they can switch over to the oem for a backup in the field.

I'd like to figure out a setup that would utilize the oem pump as a txfr pump from the aux tank to the main, and have it still available as a backup in case the fass quits. Theres a couple minor problems to work out, but theres got to be a slick way to do it.

Anyways, for those that haven't already, fix the fuel problem now before your lift pump dies, save your expensive VP44, and have a backup all mounted up & ready to go..

 

But the motor looks so nice with all the junk off the side of it and a nice little chrome blockoff plate on the block.

 

Alpine I just couldn't live with it anymore, the fact of your metric lines being bigger / flowing more than mine. So as of last week, I now have a new fuel sender unit and... An8 lines that are plumbed inside the tank as well. True 3/8 only equals .375, but it is a true passage from stern to bow now. The OEM tank fitting IMO is the biggest restriction in the system, well not in mine anymore.

 

Oops, typed that wrong and did not notice, I meant to say that I do not have the engine in yet. In the process. Takes twice as long to keep running for parts than getting the work done. Also had to rebuild the rear axle. I bit off a little more than I planned with putting in the air compressor with it. Had to find and get a custom power steering pump built for the Dodge pressure. I will still have to find a frame stretcher, I'm about 1/4 inch too long between the front of the engine and the motor mount. I spent at least four days just getting the pump and fitting together to mount the mess in the truck. I also ended up making the fitting from the power steering hose and the pump. Also have to make a fitting for the fuel feed as the AN does not fit between the compressor and the VP. There are two sizes of banjo's in the assortment that I have here, using the larger one and silver soldering a 3/8 pushon to it that will extend past the compressor. Now, one more trip to Birmingham for the support bracket that is ordered at Cummins. Planned to run Saturday, but looks like I won't make it.

 

Hi Boys I need some help. I was out in Bakersfield today purchasing a fifth wheel RV. On the way out there the truck started bucking a little bit and then it got worse. After I left the RV dealer and forgot about it. The truck ran fine for a few miles then she started in again. Is this a lift pump problem or is it a fuel filter.

Thanks in advance Bill

 

Size envy

did you notice anything going with the bigger lines?

AlpineRAM

 

You need to hook up/ monitor a fuel pressure guage to varify its a fuel supply issue and to trouble shoot whether its the filter or supply/lift pump.

 

Well in all honesty... No, after initial install my fuel pressure was up a couple pounds but perhaps it was becuase I was parked on an angled driveway. I have monitored the pressure for a couple weeks and it's the same as before. But for what ever reason the truck is running better than ever, I think it looks forward to drag racing as well!

 

Before measuring fuel pressure, there are a couple of thing you can try:

If the truck is bucking or surging, I would first reset the APPS: https://www.dieseltruckresource.com/...n&onlynewfaq=1

If that doesnt work, replace the fuel filter.

If that doesnt work, you will need to check the pressure supplied by the lift pump. In this case you'll want to measure prefilter and should have at least 9 psi at idle and 6-7 psi at WOT. If you do a search for lift pump, you'll have more than enough info.

Good luck.

 

Hey Opie,

I did find one error in your mental calculations. A short 5/16" line feeding a long 3/8" line will flow more than the combined length of 5/16" line. Granted, the combined length in 3/8" will flow more than either.

Just an observation...I enjoyed reading the "debate" and learned some things.

Kinda weird aout the warm fuel producing economy, I wouldn't have thought of it. On gassers, drag racing, it's the opposite. You want to cool the fuel to lessen preignition and hence can advance the timing or up boost pressure. Perhaps that's where the increased power on gassers comes from and warm fuel would be better sans the preignition problems. Compression ignition has it's novelties.

 

I have a hunch that it has more to do with the flow charistics of diesel fuel than proper combustion. Gasoline does not have that problem.

There is a heat box for gasoline engines that works very well for economy. It consists of a heat exchanger where the heater water heats a tank with a coil in it for the gas, and a temperature sensor sets the temperature of the exchanger. Don't remember the proper temperature, but somewhere I have the plans for building it. A friend had one on and it did get better mileage. If I remember the big advantage was that the gas was at a stable temperature, regardless of the outside temperature and once jetted properly big gains were accomplished. I never got mine done.

For power at the strip, the cold box to cool the gas works differently. The cold fuel atomized in the carb cools the mixture thereby has more oxygen in the denser air.

Fords for years had a heater under the carb from coolant supply in stead of a heat riser.

 

Rattletrap1,

I was only implying that you can only flow as much fuel as your biggest restriction will allow. The supply line in the tank is a bigger restriction than the factory fuel filter assy. IMHO whether you feed the VP44 with 5/16” line or a fire hose it won’t make a difference in hp. Provided that the 5/16” line is being supplied by a pump with an adequate volume. Since you have read the entire thread I hope I got my main point out. It doesn't make sense to me to remove your factory fuel filter assy. I plan on pumping up my motor after this season. When it's done I will still be using the factory fuel filter assy.

As for hot and cold gas… It has always been my belief that cold dense fuel is for horsepower and warm gas gives better fuel economy.

While supporting cars in the drag race community, it has always been a practice to try to keep all fluid temps at a known temp for cosistency reasons. This holds true for alcohol cars as well.

 

Man, I can't believe this thread is still around. The horse is dead already.

 

Just replace everything with 1/2" galvanized pipe. Inside the tank, all the way to the injection pump. Don't even bother with the filter. How's that setup for everyone?