Fuel Pressure Gauge Installed -Good News, Bad News

[jumpjg]

Installed a 0-30 psi gauge yesterday. I tapped into the filter housing; the '99 has two 1/8" pipe thread ports on the top of the filter bracket, inboard port is post-filter. I used Mike's recommended Weatherhead needle valve feeding into a tee; pressure line to one port, Kohler engine oil pressure switch (NAPA SME 2509927S) to the remaining port to activate a low pressure warning light. Good news is all works well. Bad news is low pressure (big surprise here,eh?); 10 psi engine not running, 7-8 psi engine idling, 5 psi around town & 65 mph cruise on highway.Solution is not all that clear. Presently the truck is stock, 173k miles, seems to run fine, no starting problems, no history as to whether this is original IP/LP, or if replaced when it was done. There is some seepage at the grommet where the fuel heater wires enter the filter bracket, and there is a fuel leak from the top of the tank that went unnoticed until the tank was filled. In addition, the tank only took 25 gallons to fill when the low fuel light illuminated at an indicated 1/8 tank.I'm looking at an aftermarket LP, possibly FASS platinum, and dropping the tank to address the leak/sender problem. From what I've read I should expect that the IP's internal diaphragm is cracked, to be prepared to experience hard starting issues at a minimum with a new lift pump, and perhaps IP failure in the near future. Not sure if I should keep the OEM fuel filter to retain the fuel heater & WIF indicator, or even if repair of the leaking grommet is possible. I'm not comfortable driving it now for fear of IP failure, but what to do with the full load of fuel? Looking for guidance. In the mean time I will move the gauge to the filter inlet to look for pressure drop across the filter - won't do a thing for the IP's diaphragm, but may indicate a blocked filter & give me the faith to drive the truck until the tank is empty. Thanks for the help,Joe in St Louis

[LiveOak]

Sorry to hear of the fuel pressure problems you are having. I have posted a number of replies covering this issue as have others. The short answer is, buy and install an AirDog 150 or 165 or FASS. If you truck is stock and you plan to leave it that way, buy and install an Airtex E7153 fuel lift pump. It is not the ideal solution but will work well on a stock truck PROVIDED you install a fuel pressure gauage to alert you to a drop in pressure that is unaccceptable either due to a restricted fuel filter or marginal lift pump. The Airtex pump will deliver about 17 psi at idle and fluctuate between 12 psi and max output for normal driving. If you relocate the Airtex pump from the OEM position to the frame just below the fuel tank, it will produce about 20 psi max and produce a pressure range of the max and about 14 psi. This will change and lower some with wear and as the fuel filter gradually accumulates contaminants. Rock Auto carries the Airtex E7153 fuel pump for $122.79 currently. http://www.rockauto.com/catalog/raframecatalog.php?catalog=203&partnum=E7153&a=FR203-E7153-70510 You can purchase a big line lift pump relocation kit from one of the dealers who support this forum or from Vulcan. This is what you are looking for: http://www.vulcanperformance.com/Draw-Straw-II-1-2-in-draw-tube-and-1-2-in-pushlo-p/vpps9804.htm Again, the AirDog 150/165 or comparable FASS is the BEST solution. If you plan to modify the engine, this is the best course of action. If you will stay stock and money is an issue, the Airtex pump is an acceptable solution. It costs much less, is a direct drop in replacement of the OEM Carter style lift pump, and is a very reliable pump. Try doing a search on Airtex pumps or fuel pressure.

[jumpjg]

Great reply with regard to the Airtex fuel pump, especcially the Rock Auto link. Naturally this alternative retains the OEM filter/heater assy. I have a seepage leak at the grommet where the heater wires pass through the filter housing. Is it possible to repair/replace the grommet?If the Airtex casn develop 20 psi with the frame mounting position, is there a need to address a possible over-pressure condition with a regulator or some other device?Thanks again for the leads,Joe in St Louis

[LiveOak]

Great reply with regard to the Airtex fuel pump, especcially the Rock Auto link. Naturally this alternative retains the OEM filter/heater assy. I have a seepage leak at the grommet where the heater wires pass through the filter housing. Is it possible to repair/replace the grommet? If the Airtex casn develop 20 psi with the frame mounting position, is there a need to address a possible over-pressure condition with a regulator or some other device? Thanks again for the leads, Joe in St Louis

You can get parts and seals for your filter canister at the dealer or Cummins dealer. I am pretty sure they are dealer or Cummins only items. 20 psi is the max these pumps will put out, if you relocate them to the frame. That is not enough pressure to hurt anything. Once the engine is started, the pressure will vary according to driving conditions at some pressure less than 20. You want enough fuel pressure to open the fuel return in the injector pump which aids in cooling and lubrication. The pressures I listed are best case. With use, wear n tear, and fuel filter accumulation, these figures will almost always gradually reduce.

[98whitelightnin]

I had the same leak you have over 2 years ago and I went to the dealer and they said they no longer make the filter housing for the 98-99 trucks. He tried to sell me one of the newer housings with the plastic lid the like the 2000+ trucks use but it was like $800. I took my housing apart, cleaned it with brake cleaner and then used black rtv silicone on the o-ring and it hasnt leaked since. If your going to get a fass or airdog you wont need this housing anyway. Or you can find someone with a fass or airdog that removed their housing and see if you can purchase it from them.

[LiveOak]

My truck is a 2002. Uses a different fuel filter canister. I could not remember where I bought the fuel heater element and seals for mine when I last posted the reply to you. (living life with CRS :banghead:) I just now remember where I got them. Give Hoesli Diesel a call. They found the parts for me and at a great price. They may be able to find the correct seals you need too. http://hoeslidiesel.com/store/index.html

[Mopar1973Man]

I'll toss the 2 cents into the pot... Be aware that AirDog and FASS are the same design for the most part but the FASS is phyiscally larger and difficult to hide under a truck. As for the platinum series I'm not sure... As for a AirDog it hides behind the transfer case quite well... So consider the phyiscal size of the pump, filters, and your mounting location.

[UtahCummins]

I was having a similar issue a while back. My FP was around 7-9 psi at idle and would drop 2-3 hauling @$$. I know I may have some guys on here that have had bad luck with them or say they are not made for diesels,which they technically are not,but I will ALWAYS suggest the Holley Blue fuel pump. I bought mine brand new for $71 and changed the fuel filter and have had no problems. I now push 3-4 times as much fp psi. I mounted it to the frame and put it directly in front of the tank. They even make an inline filter if you would want to put between the tank and pump for like $10 at NAPA. I bought it but never put it on. I mounted a toggle switch to be able to turn the pump on/off(just bc the valve sticks, esp when its hot outside, when too much psi of fp is put out on initial start and makes it hard to start at 20+ psi). Fires up perfect every time and it has been 8 months+ and I have had no issues. My father in law has had the same one on his 2001 24v for 6+yrs now. Even if it goes bad...I'll buy another one. I will have had to go through 5-6 Holley Blues just to pay the same price as a FASS or Airdog(not saying they are bad, just way overpriced). It's totally up to the person and how much they want to spend at the time. Good luck!

[jumpjg]

Well it's been a busy week. I ended up going with the Airtex pump mounted in the OEM location. I was able to score a good discount coupon for Advance Auto. If you make your purchase on-line you are able to enter a discount code as you are checking out. If you enter "VISA" you can get a $50 discount on purchases over $150. They had the Airtex for $161-$50 = $111. Picked it up locally, no muss, no fuss. Another thing I learned is the early production pumps were delivered without the additional suction side elbow. I called the Airtex Tech Line & they told me the production date is listed on the name tag on the box in the lower right corner. The number in my box was 038, which translates into the 3rd week of 2008 - an early production unit. They sent me another hardware kit which included the elbow, but I was able to do the install without it.It was a little tough to get in that area of the truck, mostly because you can't get two hands down there at the same time. When removing the Carter pump, the studs backed out of the pump instead of the nuts coming off the stud. Once I overcame that, the Airtex pump wouldn't fit into position without removing the LP-to-filter fuel line first. I would have liked to replace the banjo sealing washers on the filter, but I had to reuse the old ones - luckily no leaks. The truck started without too much difficulty and the FP gauge was showing 14 psi at idle. I was actually hoping for more, so I decided to replace the fuel filter. After doing that the idle FP is 17psi. Haven't had a chance to take it out for a road test, but revving the engine only allowed the pressure to drop to 14 psi. Next Spring when the weather is better, I may move the pump down by the tank, but I'm pretty happy with my results.Thanks to all who responded & provided good suggestions. Getting more familiar with the truck & more confident in doing my own repairs.Joe in St Louis

[AH64ID]

Nice score on the pump!If you ever want to upgrade I am very fond of the Platinum. It has better filtration out of the box than the AD, and the FASS HD and the same as the FASS Titanium, with 1 less filter. The cost is also the best of all the filtered units.

[LiveOak]

It is a cramped pain in the neck for working space getting the lift pump out and reinstalled in the OEM location. My Airtex pump came with the Dorman 90 degree elbow fitting. About the only thing I had to do was very slightly bend the fuel line just a little to align with the new pump and fittings. Otherwise, everything went in place pretty well. Now that I am using the Baldwind PF7977 fuel filters which I believe are 5 micron, I find that I am replacing them about every 2,500 to 3,500 miles. Sometimes they will go a little further before I note a fuel pressure drop from normal and replace them. I buy them by the case so they are pretty cheap that way, $10.16 each plus shipping from BF Web Express. http://www.bfwebexpress.com/catalog.asp Relocating the fuel pump to the frame just below the fuel tank will raise the pressure out put about 2 - 3 psi.

[jumpjg]

AH64ID,The Platinum was what I considered at first, but with the discount I got the Airtex was a better choice for me - at this time. Are you using a Platunum pump now? If so, which GPH did you go with? Seems that the 150GPH unit costs the same as the 95 - not sure what the difference is or why one would opt for the 95. One person told be the only difference is a spring - not sure if I buy that. Pressure maybe, but flow? I may go that route in the future, not so much for the pressure/flow but rather for the air removal factor.Thanks for your input,Joe in St Louis

[AH64ID]

I am still running the stock pump. I am not 100% sold on the need for air removal, but at the price of the platinum I don't think you can go wrong.

[jumpjg]

Live Oak, For a fuel filter I got a part number from Geno's garage (Fleetguard) & talked to a local place called Truck Pro - an auto parts chain for big rigs. They crossed the number to a Baldwin PF7751 (earlier fuel filter canister) & cost was $12.35. BW Web Express sells them at $15.72 each (case price) - still much better than NAPA who wanted $30!Thanks,Joe in St Louis

[LiveOak]

I meant to mention that one reason your fuel pressure figures may be a little bit off from mine is that we installed the Vulcan Big Line Kit on the truck since I had that parts for it when I installed the Air Dog on my truck. We just swapped the Big Line kit over to the wife's truck. This completely did away with all of the banjo fittings which are a restriction to fuel flow in and of themselves.