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Engine/Transmission (1998.5 - 2002) FASS, 1st Impressions
- Thread starter Mundgyver
- Start Date
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I dont know how everyone else installed the system but what I did was eliminated the old line and fitting completely.
Went to the part store and bought myself a line press fitting and a fitting that screwed into the pump, eliminating the bango fitting.
To install your fuel pressure gauge, I went towards the firewall approx 2 ft, cut the line and installed a "t". WORKS GREAT.
I was a little anal about drilling things out. The flair fitting at the pump and a push type/pressure flair on the line works great!
System over all is great to install, great directions.
Went to the part store and bought myself a line press fitting and a fitting that screwed into the pump, eliminating the bango fitting.
To install your fuel pressure gauge, I went towards the firewall approx 2 ft, cut the line and installed a "t". WORKS GREAT.
I was a little anal about drilling things out. The flair fitting at the pump and a push type/pressure flair on the line works great!
System over all is great to install, great directions.
When you get your kit, lay it out and look for the fittings that will be used at the VP. You will see the flair fitting that is restricted. It will be very obvious. Just size up a drill bit on the inlet side to it in a drill press. What this will do for you, is to allow for and increase in volume of fuel for the VP. It's a good thing 
The current banjo bolt on the VP will go away.
The current banjo bolt on the VP will go away. Thanks Mundgyver! Looks like Brad has it fixed for me - even though I hadn't mentioned it to him directly. Guess he was just monitoring the forum. This guy's on the ball!
Best way to lower Fuel Pressure?
With the FASS I'm seeing 16psi at idle, 15. 5 cruising the freeway, and 15 at WOT.
Runs great, but doesnt seem to like the higher starting pressures, as it sometimes takes a while to fire off. It always used to start quick w/ the oem pump.
What is the best way to lower it down to 12?
Cut the existing regulator spring down? Or get a lower pressure spring??
With the FASS I'm seeing 16psi at idle, 15. 5 cruising the freeway, and 15 at WOT.
Runs great, but doesnt seem to like the higher starting pressures, as it sometimes takes a while to fire off. It always used to start quick w/ the oem pump.
What is the best way to lower it down to 12?
Cut the existing regulator spring down? Or get a lower pressure spring??
Shortshift, call Brad and get another spring. They make two springs for this FASS, one is for 24 valve and one is for the 12 valvers that require more pressure.
I will tell you a little story about mine. I had fuel pressure gauge problems as I thought I had low pressure from the FASS. My gauge would not move from 9 lb. I called Brad, he sent me a stronger spring, one for the 12 valvers, I installed it and still only had 9 lb. according to my gauge (Dipricol). So, I took it to the dealer that had a mechanical gauge and we hooked it up. Turned out I was and had been running on 26. 5 lb of pressure. WOW. I had heard that the truck was to be hard starting if you had too much pressure. I noticed nothing. Go figure. Since then I had reinstalled the original spring, while we had the mechanical gauge on it, and it was then at 11-12 at idle. Turns out I had a bad isolator. Thought I'd pass that on to ya.
Don
I will tell you a little story about mine. I had fuel pressure gauge problems as I thought I had low pressure from the FASS. My gauge would not move from 9 lb. I called Brad, he sent me a stronger spring, one for the 12 valvers, I installed it and still only had 9 lb. according to my gauge (Dipricol). So, I took it to the dealer that had a mechanical gauge and we hooked it up. Turned out I was and had been running on 26. 5 lb of pressure. WOW. I had heard that the truck was to be hard starting if you had too much pressure. I noticed nothing. Go figure. Since then I had reinstalled the original spring, while we had the mechanical gauge on it, and it was then at 11-12 at idle. Turns out I had a bad isolator. Thought I'd pass that on to ya.
Don
Thanks for that Git,
So, if you run an isolator, you should have the following:
1. ) Include a schrader valve close to the VP44.
2. ) Keep a mechanical gauge in the tool box.
Will call Brad and check on getting a lower pressure spring. I do know that he was initially sending out units w/ the lower pressure springs, but I guess there were alot of requests for higher pressure, so he started sending them out w/ the higher spring.
You just cant please everyone!
It will be interesting to see if throttle response changes w/ lower pressure. Sure is smoother at 16 +/- 1 over the OEM pump's 10 +/- 9.
So, if you run an isolator, you should have the following:
1. ) Include a schrader valve close to the VP44.
2. ) Keep a mechanical gauge in the tool box.
Will call Brad and check on getting a lower pressure spring. I do know that he was initially sending out units w/ the lower pressure springs, but I guess there were alot of requests for higher pressure, so he started sending them out w/ the higher spring.
You just cant please everyone!
It will be interesting to see if throttle response changes w/ lower pressure. Sure is smoother at 16 +/- 1 over the OEM pump's 10 +/- 9.
Last edited:
I'm looking to either move my lift pump to the rear, or get a FASS system.
New lift pump costs what $75?
new pump for the FASS, alittle under $300.
I still need to know why this pump is so much better than the carter or holley. I can put 2 filters inline with a relocated pump for alot less than $550. It looks like a great product, don't get me wrong. But I could replace 3-4 lift pumps for the price of this FASS, which could fail in 50,000 miles too. why did cummins go to an electric pump anyway?
wish I could put a mech lift pump on this ISB.
New lift pump costs what $75?
new pump for the FASS, alittle under $300.
I still need to know why this pump is so much better than the carter or holley. I can put 2 filters inline with a relocated pump for alot less than $550. It looks like a great product, don't get me wrong. But I could replace 3-4 lift pumps for the price of this FASS, which could fail in 50,000 miles too. why did cummins go to an electric pump anyway?
wish I could put a mech lift pump on this ISB.Shortshift,
Concerning the higher pressure at startup, did your FASS plug right into the same connector that your OEM lift pump used, or are you using an add-on relay that goes right to the battery?
Reason. . I thought that the ECM(?) pulsed the votage to the lift pump prior to starting and then went to solid 12 volts after it was running. Seems like this would result in lower pressure for the FASS as well. Maybe not low enough though?
Concerning the higher pressure at startup, did your FASS plug right into the same connector that your OEM lift pump used, or are you using an add-on relay that goes right to the battery?
Reason. . I thought that the ECM(?) pulsed the votage to the lift pump prior to starting and then went to solid 12 volts after it was running. Seems like this would result in lower pressure for the FASS as well. Maybe not low enough though?
I just got my FASS on this weekend. I thought about moving my stock pump, or adding an aftermarket, but I figured it would be easier for me to spend the $$$ and go with the FASS.
So far I like the setup, good pressure, hopefully no more worries, however there are a few things I did not like:
1) The fact that I was going to have to shut the truck off to fuel it. I fixed this problem by not using the vent tube as a return line, I added a new fitting to the tank, and now there is no problem.
2) I don't like that the whole unit is held up by two bolts, this could have been an instalation error on my part, but I don't think so. The whole unit is somewhat heavy, and with the vibrations on the road, I'm worried about the unit not staying put. I will be fixing this but ran out of time this weekend.
3) The last one is more my own fault, but I don't like that I have a 15# fuel pressure guage and the needle is always pegged. This is a good thing, but I will probably replace the spring. I would like to keep my pressure around 12-14. I dont like the fact that the needle is always pegged because now I don't know if I'm getting too much pressure.
Other than that I like the unit, to me it was worth the money.
So far I like the setup, good pressure, hopefully no more worries, however there are a few things I did not like:
1) The fact that I was going to have to shut the truck off to fuel it. I fixed this problem by not using the vent tube as a return line, I added a new fitting to the tank, and now there is no problem.
2) I don't like that the whole unit is held up by two bolts, this could have been an instalation error on my part, but I don't think so. The whole unit is somewhat heavy, and with the vibrations on the road, I'm worried about the unit not staying put. I will be fixing this but ran out of time this weekend.
3) The last one is more my own fault, but I don't like that I have a 15# fuel pressure guage and the needle is always pegged. This is a good thing, but I will probably replace the spring. I would like to keep my pressure around 12-14. I dont like the fact that the needle is always pegged because now I don't know if I'm getting too much pressure.
Other than that I like the unit, to me it was worth the money.
I also now have my FASS installed and really like it. The change in performance is subtle, but the difference is there. It's quieter too. The biggest benefit being that I now have dependable pressure to the VP44.
I also qustioned the two bolt mounting, but the bracket was more than heavy enough. I'll keep an eye on it, but think it's OK. I added some flat washers and Lock-Tite to the threads just to be sure nothing rattles loose.
Pressure before was 8# prior to starting (after bumping the starter) and near 0 when running. It is now 14# before start and at idle. 8-9# at WOT.
I'm a happy customer and pleased with the product so far.
One tip. When the instructions suggest oiling the push-lock fittings, do it. Pretty easy to push on with oil and pushing straight down. A good deal more difficult with the pump assembly in place.
Rcommend this one! Thanks to Brad at FASS!
I also qustioned the two bolt mounting, but the bracket was more than heavy enough. I'll keep an eye on it, but think it's OK. I added some flat washers and Lock-Tite to the threads just to be sure nothing rattles loose.
Pressure before was 8# prior to starting (after bumping the starter) and near 0 when running. It is now 14# before start and at idle. 8-9# at WOT.
I'm a happy customer and pleased with the product so far.
One tip. When the instructions suggest oiling the push-lock fittings, do it. Pretty easy to push on with oil and pushing straight down. A good deal more difficult with the pump assembly in place.
Rcommend this one! Thanks to Brad at FASS!
Following up on this:
Have run the Fass for about 3 months now, and have a couple observations (on my truck only - your results may vary).
1. Truck is more consistant. Smoother all around, and always strong & very "torquey" at any RPM, in any situation. It used to be more "moody", as some days it would even sound different than others. Now its consistant. This thing pulls.
2. Pressure is very stable, even when purposely running the fuel level in the tank low, retained the OEM filter/heater inline (fuel line upgrade from that to the VP), can only pull it down 1. 5 psi. (DD3's+VA / about 350HP).
3. It still smokes, dont think there has been a reduction.
4. MPG's are about the same.
5. The quieter motor is probably due to not having the OEM pump running up under the hood anymore, as that is where it sounds quieter from.
6. My VP44 doesnt like higher pressure, and is hard to start warm when pressure is 15 or higher. Have tried settings from 10 - 22 psi, and found it is happiest at 12-13. Always fires quick again. No more hard starts.
7. The Fass fuel filter weeps fuel. Havent been able to stop it yet. Its not bad, and doesnt drip, but its close to it.
8. Anytime after making a change, it takes about a week to get all the air purged from the system. Might have a hard start or 2 for a few days. Then goes away. .
9. If you plan to adjust your pressure spring, make sure your tank is less than about 1/2 full, or when you remove the return fitting, the fuel level is higher than the fitting, so you have a constant siphon through the pump, from the tank, and a diesel fuel bath! Much easier when the fuel level is low - trust me.
10. It did fit on my 2000 short box 4x4, but is pretty tight in there. I did not enjoy the install.
Bottom line: Very Satisfied w/ the FASS. It did take some fiddling to get there, but now I feel this is "a" logical attempt to improve our fuel pump fiasco. Its about as good as its going to get. If the VP dies, it wont be due to fuel starvation.
One alternative I would have liked to try, would be to mount 2 (pumps of your choice) in a top/bottom configuration on the frame, and have the ability to quickly change pumps by moving the lines up or down to the other pump, and moving the wiring harness.
But this FASS is a beefy unit, and we all can appreciate that. So far it has operated flawlessly.
Hope this helped someone. over & out. '73s O. M.
Have run the Fass for about 3 months now, and have a couple observations (on my truck only - your results may vary).
1. Truck is more consistant. Smoother all around, and always strong & very "torquey" at any RPM, in any situation. It used to be more "moody", as some days it would even sound different than others. Now its consistant. This thing pulls.
2. Pressure is very stable, even when purposely running the fuel level in the tank low, retained the OEM filter/heater inline (fuel line upgrade from that to the VP), can only pull it down 1. 5 psi. (DD3's+VA / about 350HP).
3. It still smokes, dont think there has been a reduction.
4. MPG's are about the same.
5. The quieter motor is probably due to not having the OEM pump running up under the hood anymore, as that is where it sounds quieter from.
6. My VP44 doesnt like higher pressure, and is hard to start warm when pressure is 15 or higher. Have tried settings from 10 - 22 psi, and found it is happiest at 12-13. Always fires quick again. No more hard starts.
7. The Fass fuel filter weeps fuel. Havent been able to stop it yet. Its not bad, and doesnt drip, but its close to it.
8. Anytime after making a change, it takes about a week to get all the air purged from the system. Might have a hard start or 2 for a few days. Then goes away. .
9. If you plan to adjust your pressure spring, make sure your tank is less than about 1/2 full, or when you remove the return fitting, the fuel level is higher than the fitting, so you have a constant siphon through the pump, from the tank, and a diesel fuel bath! Much easier when the fuel level is low - trust me.
10. It did fit on my 2000 short box 4x4, but is pretty tight in there. I did not enjoy the install.
Bottom line: Very Satisfied w/ the FASS. It did take some fiddling to get there, but now I feel this is "a" logical attempt to improve our fuel pump fiasco. Its about as good as its going to get. If the VP dies, it wont be due to fuel starvation.
One alternative I would have liked to try, would be to mount 2 (pumps of your choice) in a top/bottom configuration on the frame, and have the ability to quickly change pumps by moving the lines up or down to the other pump, and moving the wiring harness.
But this FASS is a beefy unit, and we all can appreciate that. So far it has operated flawlessly.
Hope this helped someone. over & out. '73s O. M.
Guys, IT IS TOO EXPENSIVE :--)
Shortshift, Have you talked to Brad about the filter constantly weeping. I haven't looked at their flow schematic, but usually the water seperator is on the suction side and the filter is on the pressure side and if you have any leakage on the suction side you can get air in also. Possibly an uneven seal surface or the center thread portion could be slightly crooked. I've talked to Brad before and I think he would be concerned.
Yeah, but the bling factor is definitely there...
Billet is expensive. Period.
I put mine on this past weekend, and I am happy. I have a Banks Ottotmind on mine as part of the Stinger kit, and I had been having a little stutter under full throttle on a long uphill on the way to my house. I speculated that this came from marginal fuel pressure for a failed/failing lift pump, because now I can Ram it all the way up the hill with the pedal all the way on the floor and it runs smooth and strong.
It's a clean kit, if I had to gripe about one thing it would be the fact that I feel the instructions should say to bleed the fuel line until you see fuel flow at the 90 degree fitting that feeds the VP44.
I didn't do this initially and just cranked the hell out of my starter and couldn't get the engine to fire. As soon as I bled the fuel line, I was back in business.
Nice setup, I reckon.
Fass
But how much money is the VP44??
But how much money is the VP44??
Just installed mine on 5/10. I plan to use the existing fuel supply line to plumb my mechanical fuel pressure gauge.
Wiredawg
TDR MEMBER
quick connect help
hey guys:
I'm installing a FASS on my 02 3500. i spent a couple of hours trying to get the quick connect off the fuel tank without any luck. Anyone have any advice or better instructions. One handicap is I have custom side steps welded to the frame where I can only get one hand on the line.
Thanks for any suggestions.
Wiredawg
hey guys:
I'm installing a FASS on my 02 3500. i spent a couple of hours trying to get the quick connect off the fuel tank without any luck. Anyone have any advice or better instructions. One handicap is I have custom side steps welded to the frame where I can only get one hand on the line.
Thanks for any suggestions.
Wiredawg
Tank
When I had to get on top of the tank I loosened the bolts to the tank and dropped it down some and was able to get in there. DON'T TAKE THEM OFF ALL THE WAY.
When I had to get on top of the tank I loosened the bolts to the tank and dropped it down some and was able to get in there. DON'T TAKE THEM OFF ALL THE WAY.
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Issue 128 – Digital Version
Digital Magazines
FREE!
TDR Test Drive - Digital Edition
Renew
Subscribe
Gift Subscriptions
Back Issues
Subscription Status
Address Change Form
Buyer's Guides
Ram Diagnostic Trouble Codes
The Perfect Collection
The Perfect Collection Vol. II
TSB Updates
Dodge/Cummins Historical Overview
Cameron Collection
What Makes Us Tick?
Product Showcase
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