Hello I installed a Fass fuel pump in my Winnebago Ultimate Freedom 83 Cummins 350 horse as shown in first diagram on this post. Fuel from tank goes to Fass pump which is where my primary filter was. From there fuel goes thru stock lift pump to secondary filter with water sensor in it and from there to caps pump...is this acctable?
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Hello I installed a Fass fuel pump in my Winnebago Ultimate Freedom 83 Cummins 350 horse as shown in first diagram on this post. Fuel from tank goes to Fass pump which is where my primary filter was. From there fuel goes thru stock lift pump to secondary filter with water sensor in it and from there to caps pump...is this acctable?
Personally, I think people do it this way because it’s easier. I don’t think running the fuel through the lift pump is the way to go. Just bypass it, less chance of a fuel leak and less restrictions.
Bill
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2003 Country Coach Intrigue 36'
Cummins ISL 400
Personally, I think people do it this way because it’s easier. I don’t think running the fuel through the lift pump is the way to go. Just bypass it, less chance of a fuel leak and less restrictions.
Bill
My OEM lift pump developed a leak. This is partly or entirely what lead to the demise of my vp44. Getting rid of the original lift pump is the main reason I put on the fass pump.
Went to the local Cummins dealer. Checked out my type of lift pump, there is a diaphragm/check valve that allows fuel to bypass when the lift pump shuts down so the caps pump can draw the fuel through it from the tank. I talked to Fass they said it was acceptable to push through this type of pump as the caps pump has to pull through it. I would’ve had to do a lot more work to bypass it also if I need to use the old lift pump I switch two lines and two wires and I’m back to stock. I also installed my fuel pressure gauge in the filter which has the water sensor, this is the filter after the lift pump just before the caps pump. Seems to be working fine, reading 16 pounds of pressure, drops to 15 when I put my foot into it. Lots of battle scars during this project my skin isn’t what it used to be! Thanks for all the info everyone posted this is a great forum!
2000 Winnebago ultimate freedom Spartan chassis 350 hp Cummins 98,000 miles and still going
Made my test run up to the local mountains, fuel pressure was holding at 15 to 16 PSI. Thought I was doing good till I looked down and saw a check engine light, pulled over looked in Silverleaf diagnostics and saw multiple fuel injection codes. Switched hoses back to stock finished my trip pulling some steep grades and the engine ran fine so I guess it’s not wounded. I may or may not continue this project bypassing lift pump at a later date. At least now I have a fuel pressure gauge showing 15 psi when the lift pump is running
Made my test run up to the local mountains, fuel pressure was holding at 15 to 16 PSI. Thought I was doing good till I looked down and saw a check engine light, pulled over looked in Silverleaf diagnostics and saw multiple fuel injection codes. Switched hoses back to stock finished my trip pulling some steep grades and the engine ran fine so I guess it’s not wounded. I may or may not continue this project bypassing lift pump at a later date. At least now I have a fuel pressure gauge showing 15 psi when the lift pump is running
Made my test run up to the local mountains, fuel pressure was holding at 15 to 16 PSI. Thought I was doing good till I looked down and saw a check engine light, pulled over looked in Silverleaf diagnostics and saw multiple fuel injection codes. Switched hoses back to stock finished my trip pulling some steep grades and the engine ran fine so I guess it’s not wounded. I may or may not continue this project bypassing lift pump at a later date. At least now I have a fuel pressure gauge showing 15 psi when the lift pump is running
So your back to the stock configuration? What codes were thrown? Did you disconnect the power to the lift pump when you did the Fass conversion?
Bill
__________________
2003 Country Coach Intrigue 36'
Cummins ISL 400
Yes I’m back to stock going to stay that way take my chances with the old system and yes bypass the lift pump with a relay. The pump was a titanium series 95 gallons an hour 17 psi. Codes injector cylinder number 19 frequency error, injector cylinder number 18 high reading, injector cylinder number 18 low reading, and a few other codes with injection system.
Accurite: You went to a lot of trouble to install a FASS Titanium Series pump with 2 additional filters.
* Can you elaborate on your those error codes a bit more? What were they again, and are you saying those codes went away after you returned your fuel lines to a stock fuel delivery configuration?
* What year is your coach? Model? Engine type? Chassis type?
* When did you add the Silverleaf System?
* Are those error codes from a scan tool?
* Did your engine experience an engine "de-rate" when these codes triggered your check-engine light? Any loss of power?
* Did the check-engine light go away at any point while the FASS pump was installed?
* Can you provide us with pictures on how your mounted the FASS TS pump in your engine bay?
* Did you have any trouble installing the "Y" yoke-adapter in your fuel filler neck? And was your slide out a concern? Mine was very tight. Can you include pictures of this area? It might be helpful to the rest of us!
It sounds like your code descriptions were due to too much pressure. Is that right?
I would have called FASS to ask them about how to adjust he spring in the fuel out-port, because that is what is used to set the FASS "TS" pump pressure. ... Let us know what you do. Thanks!
My TS pump always reads 15-16 PSI. I have never seen 18 PSI, and I have a remote gauge in my cockpit. (Your oil filled gauge on top of your filter is probably more accurate.) However, I do see my fuel pressure occassionaly hit 17 PSI and under load I see 14-15 PSI now that I have over 8,000 miles on my filters. This may or may not be relevant. I only mention it, because I'm still trying to decide if fuel pressure from the FASS TS port can indicate when the filters need changing? But I am told by FASS you cannot assume a drop in PSI is indicative of a restriction in the filter. However, I think it's possible that under acceleration you will see more of a PSI drop as your fuel filter go from new to 30% to 50% restricted; and by then your filters will be 2 years old that's about the time I will change them. TBD
Please refer to the diagram below for how I installed my FASS TS Pump in my Winnebago Itasca - Freightliner Chassis; which was based on a 2-filter set-up before I installed the FASS "TS" Pump. (See .pdf for installation instructions attached.)
In this case I just removed the primary filter and mount (on the left side of my engine bay) and installed the FASS TS Lift pump in it's place. And then I had Freighter install a relay (using the right wire harness) to trick the ECM into thinking there is a "load" on the other end.
How did you connect your 2 ECM wires to the relay? Cut and soldier or did you get a compatible wire harness so you know you have good connections?
FASS TS LIFT PUMP NSTALLATION OPTIONS
*Most RV owners with an Independent Front Suspention (IFS) up front do not have room to install the FASS TS Lift Pump by the tank; and even if they did... you cannot access the top of the tank in a Freightliner Chassis.
* Monaco owners with a Spartan Chassis should have access to the top of the fuel tank and can more easily bypass the Cummins Lift Pump in the engine bay. In these installations you should follow the "pink highlighter" in the drawing.
I frankly have nothing but good things to say about my FASS TS Pump installation. And after 8,000 miles I have never once had an engine check-light problem. I also carry a portable scan tool and have checked my ECM for soft error codes and there are none.
My feedback is all positive. I even think the FASS TS "fuel polishing/re-circulation benefits" mean I no longer have any algae concerns in my tank!
The first diagram is for a Winnebago Itasca - Freightliner Chassis (with IFS).
The second diagram I think was provided to me by TR4, where he shows how he would run the fuel deliver lines and bypass the lift pump all together. Monaco's with a Spartan Chassis will have an easier installation if they can mount the FASS TS Pump near their fuel tank... and can access the top of their fuel tank where they can insert a "T-Fitting" to handle the FASS fuel return line. Then you can disconnect the old fuel out line from the tank to the the lift pump manifold (and just plug it). Then you can run a 38' fuel line from the FASS TS out fuel port DIRECT to the injection pump... and bypass the lift pump completely.
Accurite: Do you have 2 or 3 fuel filters in your setup?
Updated FASS-TS Pump Installation Tips (See attached .pdf)
Attached is an updated .pdf on how I installed a FASS-TS pump in my 2004 Itasca "Horizon" 40AD, with a Freightliner Chassis, and 2 fuel filters.
If you have 1 filter, chance are you just need to remove it and install a FASS or AirDog pump in it's place.
It also looks like the better pump to order from a FASS distributor (like Parley's Diesel) will be the 100 GPH vs. the 95GPH pump I ordered, because the 100GPH kit includes longer power and ground wires needed to reach your engine battery.
Note: AirDog-II-4G pump may also be another option, but if you are sold on the benefits of FASS-Fuel-Polishing, then stick with the FASS "constant volume" pump and order a 2" silver color fuel Return Manifold you then will splice into your fuel filler neck... and 38' of blue FASS fuel line... ordered direct from FASS.
AirDog Electric Pump (An Alternative To FASS-TS-95GPH)
Another owner just installed an AirDog-II-4G-150GPH pump in his 2002 Nemar/Spartan Chassis (8.3L) and he is quite happy with his installation. For more information you can visit his thread at:
There are several differences between the AirDog "demand flow" pump and the FASS-TS "constant volume" pump you might look into.
Both pumps achieve the same primary goal of providing positive fuel pressure to the injection pump (CAPS in this case). However, the AirDog returns ~10x less fuel to the tank. Therefore, the AirDog installation may be easier if you don't want to run a 38' for a fuel return line to the tank -- like you have to do with the FASS pump.
On the other hand, the FASS offers "fuel polishing" benefits over the AirDog, if you buy into this sort of thing? I tend to think it's worthwhile, but that's just my opinion.
The AirDog pump costs a bit more too, but the FASS fuel return line will cost ~$125 more. So both pumps cost about the same in parts. However, the AirDog may save you 2 hours of installation time.
Fuel Gauge Note: You really do not have to run a digital fuel pressure gauge to your dash. This is a desirable option, but it will cost you $150 and another 2-3 hours of installation time vs. buying a $15 gauge on Amazon and a 10mm to 1/8"NPT adapter so you can mount an oil filled gauge on top of your filter block.
In both cases (AirDog & FASS) you need to disconnect the electrical wires from the ECM to the Lift Pump. So unfortunately, that will not change.
Attached is an updated schematic and your choice of oil filled fuel gauges. (On Amazon, you can pick on facing up or facing the side).
OK,
I am about to start getting the pieces together to install the FASS pump, before I end up having to replace the CAPS system, but I have a few questions.
I am thinking about installing a Davco filter at the tank and then mounting the Fass pump. If I do this, do I need the titanium series with the filters, or just the pump?
OR
Do I just mount the titanium 90GPH pump with filters at the tank, eliminate the primary filter in the rear compartment, and the filter on the motor? or just the primary filter and leave the secondary filter that is mounted on the motor?
(it looks like the titanium filters clean to 2 or 3 microns, just like the secondary Cummins filter does?)
Or do I need to leave the second OEM filter on the motor?
I see that the Titanium series pumps have a return on the housing, do I plug that and keep the original return system in tact from the original pump manifold?
90 GPH and 17 PSI is really not high pressure can I get by with steel, aluminum, or copper line for the main sections and use the appropriate (flared) end fittings and hose clamps? or do I need to have fuel lines made up with crimped ends to eliminate leaks?
I will probably run new lines because mine are 17 years old, do you recommend running feed and return?
What diameter line do I need? 3/8, 1/2, or 5/8 inch? Do I need the same size for both feed and return?
I am sure that there will be more questions as I get further into this, so thanks ahead of time
Jim
I just completed an Air Dog system as posted in the Cummings section. Your fuel lines will be fine unless you have damaged lines. You should have 1/2” lines to primary filter (8AN). From lift pump to secondary filter, mine was 10AN or 5/8 hose. I chose to run 5/8” from AD pump to secondary filter. My first filter is a 10 micron, second is a 6 micron and filter on the side of engine is a 2 micron. My fuel pressures at idle is 23psi, running down the highway, fuel pressure is 20-21 psi, climbing a 6 degree hill pressure is 19 psi. My pressures vary because the AirDog pump is a demand pump and only pumps what the engine requires and no separate return line to tank; just tee into caps return line at the transfer pump manifold.
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Silence in the face of evil is itself evil. God will not hold us guiltless. Not to speak is to speak, not to act is to act.
2000 coachmen santara 370 5.9 cummins isb
Thanks for all the info everyone posted this is a great forum! 
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