Engine/Transmission (1994 - 1998) Fuel Line Questions

[GGuion]

I have a 98 12 valve 4 wheel drive, 5 speed.

I want to replace my fuel lines, they have never been replaced. I see that most people go to larry b's and buy the lines that he sells. Is this the best method or should the lines be replaced all the way to the tank with marine grade rubber lines. also I want to ask about the fuel lines under the hood, for instance the soft rubber line behind the filter, where do u get a replacement for that, and what about replacing the lines inside the fuel tank, where do u get those. Thanks

 

[Vaughn MacKenzie]

Hi GGuion, welcome to TDR.

Are you going for quite a bit of HP? If under 400 or so no need to replace the metal part of your lines or what is in your fuel pickup. If you have a lot of miles or have gotten bad fuel before it may not hurt to drop the tank to see if the prefilter screen on the pickup assy is cruddy.

For your fuel line hose order TR38 from Larry B, for your smaller return hose it's 5/16 which is PN TR516 from Larry B. Larry B's Fuel hose

Also if you are doing fuel line maintenance on your truck:
-Service your prefilter, get the O-ring & filter screen kit from Cummins Fuel Pre-Filter Cleaning on Ram/Cummins
-While servicing your prefilter inspect your fuel heater to see if it shows signs of melted electrical connector or fuel residue caused by leaking. If so throw it away and get a new one, or go without the heater (just screw the filter bowl back on without the heater puck).
-Look at the 90-degree rubber hose going from the prefilter piece to your lift pump to make sure it looks good & isn't leaking anywhere.
-You might also remove the hard fuel line where it connects to the prefilter assembly to make sure the square-cut O-ring is OK.

This might seem like a fair amount of maintenance but these areas are often neglected and become problem spots if not addressed at some point.

This is a good website with diagrams and more good info on 2nd Gen trucks: Fritz Ram Diesel

Have fun!

 

[vsimkus]

I just went through this. Be prepared to do the brake line going to the rear too. When I was the removing the original metal fuel line that rusted through, I accidentally broke the brake line. It was a good thing that it broke then as it was paper thin.



I would plan on replacing the fuel tank pickup, as Vaughn mentioned, even without any horse power upgrades. If they're metal chances are they're on the verge of failing.



Depending on the mileage you might want to consider addressing the fuel level sender. At 260k mine is looking like it's getting ready to go quit.



Be ready for a nasty job - diesel and rust everywhere

 

[MHalloran]

Last year on my 96CC I had to replace the following: Supply & return fuel lines (rotted out) from engine to fuel tank using the hose Larry B sells, the actual fuel module itself cuz most of the top of it where the hoses attached to had rotted out. Had to buy this from the dealer (ouch). Wasn't cheap. Lifted the bed for this. 8 bolts & a grounding strap, unplugged tail-light harnesses & got 3 friends to assist in the lift. 8 foot bed wasn't exactly that light. Since the bed was off I checked the brake line that ran parallel to fuel lines to find this was also rotting. NAPA sold me a 25 foot length of brake line tubing for this (about 15 ft. needed) & also had to buy the double flaring tool from them (about $27) for the ends with new fittings as well. All this was really not a hard job. Full day needed. Keep in mind, about the fuel lines & system. The tiniest leak can & I'm sure will, speaking from experience, give you a hard start issue. Joe G. & also Vaughn here can back me up on this. These 2 gentlemen know their stuff. Good luck with your work. These trucks are great. It's ashame though what winter road salt will do to your undercarriage over time. Mike

 

[GGuion]

Thanks guys I appreciate the responses. And I'm keeping the truck stock.

 

[Joe G.]

Email me at -- email address removed -- for my 12 valve fuel supply system write up, how it works and how to fix it.

 

[Vaughn MacKenzie]

I guess fuel and brake lines rusting depends on where you live. . . doesn't happen around here. The lines on my 416,000 mile '96 look great.

 

[hsmith]

Another good reason for being in the Hill Country of TEXAS!! No rust problems. Now, along the coast, real problem there.