Engine/Transmission (1998.5 - 2002) Purging Fuel Lines

[Stref]

On Tuesday I will be installing Vulcan's Big Line and Pump Relocation kit. The thing that concerns me the most is cutting into the fuel line, and preventing taking a #2 bath. Vulcan's instructions say to start by purging the fuel lines. What is the best way to do this? I have read to blow compressed air through the tank feed line to push line fuel back into the tank, but I also read that there is a valve that could be damaged by doing so. Any suggestions or recommendations would be appreciated. I will be doing the installation in my driveway with all four wheels on the ground. I had contemplated using ramps on the front, which may be good for working underneath, but think that it may present some problems trying to tackle the top side work. I am also interested in putting in a fuel shut-off at the pump inlet. Any information on shut-off value resources and installation will also be appreciated.

 

[JFaughn]

I'm not sure what you were planning on cutting with but avoid using a hacksaw , use tubing cutters - the tool with the sharp wheel that you spin around the tube , then there should be an pointed pice of sheet metal that folds out of the tool and use that to scrap the inside edge off , and if any shavings get into the tube , they shouldn't be be more than an 1" inside , just shake out , both ends disconnected and blow air through ,
If its old line or may have been lying around , or may just want to make sure , brake clean from a spray can and blow out with air.
If theres any mecanizim that the lines attach to , disconnect and do as mentioned above.

 

[DLausche]

I think you can safely blow compressed air back through the line from the front. I actually replaced my whole pickup line into the tank/module and removed the entire valve assembly you are thinking of. I remember looking at the rollover valve inside the module and I do not see why it would be damaged by a low pressure from the engine side. Don't forget to take the fuel tank cap off! A very low regulator pressure setting should be enough to push it back into the tank.



I'd also recommend the shutoff valve idea so you don't get a bath when you need to change anything out like the pump... I used a simple ball valve shutoff I got from Summit. I mounted mine to my racor pre-filter with std pipe fittings. You will need to find another way to mount yours or maybe you can use a rigid pipe compression fitting and just attach it directly to the end of the steel line where you cut it off. Obviously you don't want to mount it to the pump inlet fitting because that will make it more difficult to swap the pump out when it does fail.



I tried a pipe cutter on the steel line but didn't get anywhere. Maybe 'cause my pipe cutter is old or dull. Anyways, I ended up using a dremel with cutoff wheel to cut the steel line. I would never recommend this on lines with gasoline in them though!!.



-Deon

 

[Bob Cochran]

I did all the work in the engine compartment then jacked the truck up front and put jack stand under and did the underside work. Had about a half tank of fuel and got no diesel out and did not purge lines with compressed air. I used one of those hack saw olders that you just slide blade into and it sticks out not the old huge frame. Don't use hack saw with gas but diesel is okay. I had a new mini tubing cutter and it was not going to cut steel fuel line(just scored it!!); fine for copper though.