Hi all,
I just had my caps system replaced for $$$$$$$$ and after about 1000 miles I'm getting engine codes again (I believe low side pressure code 94-FM2). Happened 1 time and cleared after I stopped the engine and restarted. Given the huge cash outlay on the CAPS this makes me nervous. I want to protect my CAPS investment so I want to replace the lift pump with perhaps an Airdog or FASS. There are signs of leaking at the lift pump meaning I could be getting air. I like the idea a positive pressure because that will keep all air out and also make it easier to spot leaks. Anyway does anyone know if there is a document that shows all the fittings and sizes in the fuel lines from tank to CAPS pump?
Oh and does anyone know of a reputable diesel mechanic in the Austin San Antonio area who will actually work on RVs?
John, when I installed my FASS system the Techs at FASS stated I did NOT have to bypass the CAPS just leave it as is and run the FASS through it. No issues for over a year now, knock on wood. I installed mine right where the original primary fuel filter was. Not a bad project. Jim.
John,
1 This would be the first thing that need to be addressed. If you haven't changed out fuel lines (you might need to put this on your to do list) the end where it terminates into the pump could be bad or just a loose fitting.
2. True just remember if you do spring a leak and you have atomized fuel spraying around in the engine compartment with a hot turbocharger you could have a problem. With that being said the FASS system is a huge help with the fuel tank as far away as it is to the injector pump.
As Jim has posted adding a Fass system isn't that big of a job about a 3 on the scale of 1-10.
Mike
We and all of our RV'ing friends have been very happy with Texas Custom Coach in Pipe Creek. Expert service and the best labor rates we have found in Texas.
I have a question about the FASS system, I see it is about $1500 vs. $10000+ for the CAPS.
I understand installing the FASS as preventative before the CAPS goes bad. If one wanted to wait until or if you had CAPS issues, could the FASS then be installed instead of repairing the CAPS?
Understanding "on the road" work is not fun.
in a word no. The caps injection pump quits, a Fass transfer pump will not help. Don't confuse the fuel transfer pump with the injection pump. I have 2 caps injector pumps fail one leaking one the Icv Injector control valve. I can tell you Cummins is plum crazy for the price of a reman caps pump.
The FASS system allows fuel to be delivered to the Caps lift pump so that the CAPS does not have to draw fuel form 20' away, the main reason the CAPS lift pump failure. Some installers will bypass the lift pump altogether. I left mine in. I'm just trying to reduce the chance of the CAPS failure. Jim.
Thanks Jim and Bruce. I was kinda thinking that's what I'd hear back. Guess in the interest of preventative maintenance, gonna have to break out a few bucks and get another project on the list.
the other thing that may help the life of the CAPS pump and ECM engine control module is changing the CAPS transit suppressor. It helps with the voltage spikes between the ICV ( injector control valve) and the ECM. If it fails it can cause failure of one or both, read $$$. It is located below the ECM accessible from below, easy to change and cheep insurance. Ask me how I know 😬😬
Bruce how many miles were on your rig before it failed ?, I ask Cummins about it and got no real answer, they said to change when it fails, I told them that was usually to late
Lost an ECM 3 years ago it was not changed then 100k or so for miles, lost injector pump last spring ( injector control valve ICV) 140k. Going forward I'll change mine every 2 or 3 years.
Thanks think I will do about the same, likely put a weather proof plug on the wires
Yeap, 130k is when my CAPS failed (according to Cummins). What I find disappointing is that no one beside Cummins seems to know what a CAPS injector pump is. I've called a ton of Diesel shops and the first question I always ask is "Do you work on RVs?" (many will not because of access issues), and the second is "Are you familiar with the CAPS fuel pump?" and most say no. Given the complexity of the thing I don't want someone whose not familiar with the system working on it. Anyway I had mine replaced billed at $235.00/hr plus the cost of the pump. It's nuts. There is a really nice video out on the interweb that explains the system in detail (link below). It's a modular system so it seems you shouldn't need to replace the entire unit.
Anyway the output side of the pump can produce pressures of up to 1700psi and the ECU is responsible timing the high pressure delivery to the injectors via a distributor and electro mechanical values. The injectors them selves are purely mechanical. Seems the system could be a lot simpler (and cheaper) with electronic injectors and a constant pressure fuel rail. A lot of moving parts in that thing. From what I understand the fuel passing through the system is not all passed to the cylinders and a good portion of it is returned to the tank. All the fuel movement is supposed to keep the system cool and given the pressures produced you can guess why it needs cooling. Again from what I understand air in the system reduces the cooling a lubricating effect of fuel which wears the pump out faster. I believe the expected life is less than 250k miles.
I'm making a appointment with Keith Reich to get the fuel lines replaced. At the time I'll have him add an extra return and install a new lift pump just for grins. Since I'll have the extra return I can add the FASS later as this is something I can do.
CAPS Injector Pump Video: https://youtu.be/xp-YuZ5uQYY?si=Z_FVYgg2mxJiJy1J
BBeane wrote:
Question for bbeane: When you had your system repaired did you have it done at Cummins?
DaBus Wrote:
DaBus: Thanks for the information. Do they do engine work as well?
Just minor stuff I think but I never asked them. Give Michael Waller(owner) a call(830-510-4224 /Address 10498 South State Hwy 16 S, Pipe Creek, TX 78063). I know they bring a tech in for major brakes. They have had difficulties keeping certified techs for that. For major engine/trans I go to S&S in San Antonio.
the first one was leaking fuel had the Freightliner shop replace it with a Cummins reman. The one that failed last year quit running on a two lane back road on Sunday afternoon. Long story short, towed to a private shop. They installed an aftermarket reman, it was defective. So had to overnight another one. Cummins wanted 10k for a reman through the freightliner dealer.
John, The FASS pump # IND165G allows you to "T" into the existing fuel return line. They also told me to leave the CAPS system as is, the FASS will work fine with it in place and working. Jim.
Area diesel service is testing a craps to p-pump conversion they have one on a truck and are tweaking the throttle actuator and con5roller that could be a fix about the same price a Oem replacement