Hello all,

Just joined the diesel crowd and am jumping in with both feet. Since this section deals with fuels, thought it would be best to post here. I have an older mid-90's Dodge with the cummins 12v. I have studied a bit on the fuel system and since the exhaust system totally consumes any usable space on the other side from the stock fuel tank, want to tie in a 2nd in-bed tank. This truck has 3 fuel lines coming off the tank. I'm guessing one being the feed to the lift pump, the other a return line from the injection pump and the 3rd smaller line being some sort of vent line or ???

At any rate, all lines disappear up under the injector pump assy and is hard to tell which is which and was wondering the best way to tie in the 2nd tank for transfer purposes.

1) Would it work to just install a valve on the 2nd tank and tie into the return line (if so, which is the return line?, and would it gravity feed ok (even if slowly), or would a person need to go to the lengths of installing an inline transfer pump to pump from the bed tank to the stock tank under the bed? (not sure best way to tie in, but would like to do it as simply and economically as possible.)

Appreciate any ideas/feedback.

Thanks!

 

I am not completely sure what is going on with your diesel engine; however, when installing a second fuel tank on common diesel fuel systems, one will have to install a 2 ported valve, so that both the fuel line and the return line are switched at the same time. Otherwise the second tank will get pumped out to the first tank via the unswitched return line.

 

Hello all,

I just found an adapter made just for diesel's with auxiliary tanks and will let everyone know how it works out. It is an inline 'tee' of sorts that goes in the fill pipe near the primary tank and has a tee bib that contains a float valve of sorts that you tie into the gravity feed from the auxiliary tank in the bed. The company said that when the primary tank fills up, the float valve in the tee closes off the gravity flow. The kit also included a manual valve to put on the bottom of the auxiliary tank so a person can turn off the feed if desired. I suppose a person could put in a electric switched valve if desired, but if it turns out it works as it should, it sounds like it will be easy to use and work with. No hassle with dual / 4 way valves, lines etc. I was kind of surprised, but was told that with diesel (but not with gasoline) gravity feed from auxiliary tanks is legal. Will let everyone know how it turns out when I get the adapter installed.