Engine/Transmission (1998.5 - 2002) Fuel return line help

[easleyj1]

Changed my oil today and discovered that I have undercoated it with diesel. It appears the rubber line portion of the return is shot. The hose feels like a small hose inside a big one? Anyway is there a better fix out there than the replacement hose from DC. I have the Vulcan big line kit laying on the bench and would like to repair the return and do the Big line at the same Time. thanks.



Jonny

 

[rweis]

I took my return line off starting at the T leg that goes back to the tank.



The structure of the return line is a about 1/4" OD nylon line loosly inside of the about 1" big line, then the nylon line is sweged inside of the metal 5/16 line that goes back to the tank.



I cut the output of the T connection just before the double swedge where the nylon line attaches. I put AN-6 line on that and 3 small hose clamps spaced about 1" apart and really honkered down on them. The return line does not hold any pressure.



I ran my return line through a couple of frame fuel coolers to get some of the heat out of the fuel. I then ran the return line to the tank filler vent line (3/4") and put in a T there and terminate the return line there. It cools the fuel and fully mixes the tank all the time.



I DID FIND OUT HOWEVER that under long heavy throttle settings towing a heavy 5er that I could begin to get some air into the fuel pickup basket in the tank. Fixed that with a DrawStraw. When I put the DrawStraw in I also found the fuel canister fuel pickup basket screens were clogged. So my fuel is cool and CAN cool the VP44 and the tank is mixed throughly and the canister fuel pckup (now DrawStraw) works really well.



My cell is 863-206-3464 and call me if you need a better explanation or I did not cover something.



Bob Weis

 

[easleyj1]

Bob, I also have the draw straw laying with the line kit. I had just about decided not to put it in as I have no power mods so... . is an-6 braided line? How hard were the mods to the fuel module? How long (guestimate) for a competent toolslinger to do the in tank mods? If the drawstraw is used I will need a filter before the LP correct? Trying to figure If I could do the return, Big Line and and the Drawstraw in one day or do I need to plan on a weekend. Thanks alot.



Jonny

 

[rweis]

I use AN-6 braided line (but that is me), but any 3/8" fuel line for diesel is fine and a WHOLE lot cheaper.



I would do the DrawStraw regardless. TOO many problems with the filter screens etc. Yes an inline filter before the LP. Just be sure it is in a place that it is easy to change and it flows pleanty enough fuel so it is not a restriction, the lp has a hard enough time as is.



GET A GASKET for the fuel canister. Many guys did not and had tank leaks.



Gutting the fuel module is easy. BEFORE I gutted it, I marked where the canister halves were in relationship to each other (slip fit) so the fuel level arm will read correctly when you are done, because it will be in the same relative verticle position.



I have an 02 and when you gut the canister where the DrawStraw goes is real obvious and the place you use the step drill down in the canister is real obvious.



Then I did the canister complete before puting in the DS and put it back in the tank. THEN I used a wooden dowel to measure where to cut the DS. Make sure you put the dowel through the hole where the DS will go to the bottom of the tank. Measure twice, cut once.



Now with everything in place you will have confidence in using the dowel to measure for the DS. Cut the DS. I put a 45* champher on my DS so it can rest on the bottom and still have clean full flow. You also have to decide which side of the tank you are going to put your fuel lines to the DS. The OEM is frame side, I put mine on the driveline side as I thought it would be easier to work on them if need be (right where the DS fitting is, there is a bed strength member exactely right there). SO my 45* cut is toward the front of the tank when the DS outlets are rotated toward the driveline.



Reinstall the tank etc etc etc. My tank straps had to get a very minor "tooling" to be able to fit into there strap retainers well without a fight.



You could do it in a day if you stayed on task.



Bob Weis

 

[easleyj1]

I really appreciate the good info Bob. I will get the needed materials next week and devote the following weekend to this project.



Jonny