Not much time in the seat yet, but I installed the cooler and fabbed up some brackets to mount the stock cooler above, for my new FASS to run through. It’s looks to be top shelf, and light years ahead of the Mishimoto. I did have to thin the support bracket on the truck a little make clearance, but no big deal. A few minutes with an angle grinder and a rattle can was all that took.
Mike’s cooler
- Thread starter N2BRK
- Start date
The output from the FASS runs into and out of the cooler. I have never run an electric pump on my truck before, just the MITUSA since about 2009, so I can't say how much it reduced temps. I know that last night I was running on cruise control at 75mph at 80*F and my fuel temp was 120* while I was running and down to 111* by the time I coasted down the off-ramp later. The FASS is a 250gph and I have a 12mm Exergy.
That's pretty cool. I recall seeing 131 normal driving in winter ( 60F ) and 145-170 in summer.
I'm not totally sure. When I did the 12mm pump, it was no longer able to supply enough at idle to show positive pressure. Once revved, it was fine. The big open cascade valve of the 12mm exergy flows a tremendous amount of fuel at idle; 40GPH! The MITUSA also had a small seal weep, so a long story short - I talked to the guy at Glacier Diesel ( he copied the idea for Cummins trucks and sells it as a Fuel Boss), and bought his pump top replace mine. Disappointingly, his actually put out less than my Opie pump when I got it! LOL. So we upped the gearing to give me full pressure at idle of 12psi. She'd go down to around 8 under max load. I drove that for a couple years and then out of the blue a few weeks ago the truck wouldn't start. Logging showed no fuel pressure. I primed the system and she started. Pressure at idle was around 4psi. Shut her off and no-start each time. New filter. No joy. I decided that either I had an issue with the pump, the regulator, or something else. I pumped her with a drill on the fuel boss and filled a jerry jug... GPH was sub-par. I went to Glacier and his supplier dried up with Covid. I decided to stop fighting and I bought a FASS 250.
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Mike sells that fantastic Setrab cooler that is made to his specs and bracketry - so yes, call him. And then call him after you get it to remind him to charge you for it! LOL. He's so nice that he shipped it and forgot to collect! Of course I called to remind him, and paid! LOL
Clarification - I am repurposing the stock Allison cooler as a fuel cooler. I used the ends off stock leaking lines that I cut up, to retain the quick disconnects and not tempt fate by removing and reinstalling fittings into the cooler!
Wally
It’s a great use of the factory cooler I think. I can agree with Mike about those fuel temps I’ve seen on these trucks with the factory coolers only in front of fuel tank. And you don’t drop any fuel pressure through the factory trans cooler for the FASS ?
I would be very surprised if I dropped pressure, but given the size of the FASS that I'm running, I'm sure the pump will still keep up.
My existing lift pump pressure gauge wiring was too short to reach back to the FASS, and a new longer wire is scheduled to come today, so I'll know for sure soon.
Just thinking to myself... I've cleaned the stack but I never went back and cleaned the fuel cooler. I suppose shame on me after 12yrs of ownership.
My existing lift pump pressure gauge wiring was too short to reach back to the FASS, and a new longer wire is scheduled to come today, so I'll know for sure soon.
Just thinking to myself... I've cleaned the stack but I never went back and cleaned the fuel cooler. I suppose shame on me after 12yrs of ownership.