Fass pump install

[Rikadoo]

So i added a “rear sub panel” my goal was to build two circuits with it. One was switched batter power the other half was steady bat positive. For the bat pos it was a no brainer iused bat power, but instead of adding to the batt “ too many rings” i took off the batt boost solinoid that whent to the engine battery. The switched i went to the air drier, it uses a key on power that stays hot while the key is on the run position only, i tapped into there an ran it back to my battery box into a Bosch relay that when energised powered the sub panel. I knew i would need other “key on powers taps” for things like “TPMS” booster and trailer tow power so i didnt want to overload that one wire to the air drier.

As for the FASS wiring i just extended the two leads (power an ground) like2 feet to ensure it would reach. I mounted the pump in place of the primary filter. For the FASS return line i removed my “rollover” valve, i then used a “T” with the roll over valve in one leg of the “T” and the return in the other.

the only other wiring i did was to include a switch into the FASS wiring harness that when held in on position would run the FASS pump so i could replace both Fass filter and prime them using the switch, eliminating the need to turn on the ignition then run back to purge them.

[vanwill52]

This does not answer all your questions but consider "ordinance" battery terminals.  They have TWO bolts.  One clamps the terminal to the battery, and there is another 3/8-16 bolt that provides ample space for multiple 3/8 ring terminals, all getting a good connection.  It is the only kind I've used for years

Ordinance Bolt Type Lead Battery Terminals (delcity.net)

Also, to power the FASS and several other items in the engine compartment, I added a continuous duty contactor with power coming from an AWG 2 lug in the rear run bay and continuing to a Blue Sea 8-space fuse block with "blown fuse" indicators.  I used that fuse block to power my EGT gage, externally mounted trans cooler fan, FASS pump and several other items.  I powered the contactor's coil from an "ignition on" signal I found in the RRB.  Since I was not sure how many places that "ignition on" signal connected to, I installed a "kickback" diode across the contactor's coil terminals.

2000 Dynasty 36

[ok-rver]

Great comments. Van, I had not seen this type of clamp. Will keep it in mind. Rick, our compartments are almost identical. I will take a look at my air dryer to see if I can easily connect to it. It comes off the same fuse buss in the Monaco 1 fuse block as the other circuits I was looking at. My diagram shows a 15 amp fuse for the dryer but does not state the function. The only electrical function I see in that great Wabco document is the heater so guessing that is it's functions. Finding Blue-Sea parts is a bit difficult right now. I have found a decent block from Autozone that I will pick up today. I have relays being delivered today so should be able to wire up over weekend. I installed a ACR a couple of months ago, great addition, and will pull power from the heavy cable off the engine battery bank cable to go up to the new fuse block. I have a ground buss strip left over from boats that I will also add.

[Rikadoo]

Hello Mike, so this is the relay i used to power the key on side of my blue sea fuse box (its funney i have put in sub panels on off road machines and i use them both exclusively) its rated for 75 amps which i am no where close to on any of my circuits an work flawlessly. Also when installed my fuel pressure gauge i needed to extend the harness from sender to gauge so i bought this wire and “rolled my own” mainly cause i didnt want coils of excess wire somehere. Im one of those wire freeks that like a clean install

[cbr046]

20 hours ago, jacwjames said:

Where/how did you determine you needed a 1.5" return line.

I missread.  - 0.5" line.  Twice as big as a garden hose would be kinda big. 

I'm mostly concerned with getting the return line back into the tank.  Right now I'm thinking a Y (with a check valve?) on the return line from the lift pump would be the ticket. 

An Option - I found a time delay relay that will energize up to 60 sec after ignition is turned.  This allows the lift pump to stay connected (no dummy relay, no extra wiring required) and let it run by design.  Or a relay driven by the lift pump signal that closes when the lift pump is de-energized.  This will work . . . . as long as the lift pump delivers.  Or just a resistor on the disconnected lift pump connector.  Question is, what the maximum resistance before the ECM turns the light on?

- bob

Edited December 31, 2021 by cbr046