Attention: TDR Forum Junkies 
When I bought my truck in January 2001 it was having the common hard start problem due to leaking fuel lines. Thanks to this site I knew what needed to be done, so I took it in to Cummins and had both the 3/8” and 5/16” leaking fuel lines replaced. This cured the hard starting problem until last week when the problem quite suddenly showed up again. I did some research here on TDR and thought for a couple of days that it could be my fuel shut-off solenoid or relay. However, I replaced my front brake pads last week and while I had the wheels off I did a good look-see from below. I spotted a problem with the 3/8” neoprene line. The Cummins mechanic had installed a line that was just a skoosh to long and it created a slight kink in the line. I wasn’t certain that this was enough of a kink to cause my hard starting, but decided it was the logical starting place for a repair so on Monday I got my seventy-year-old bones under the truck and replaced the line, making sure the new was about 1. 5” shorter than the old. I’ve got long arms so I didn’t have too much trouble reaching it from below. Yesterday it fired right up after sitting for about 20 hours.
I surmise that over time the line lost some resilience and the slight kink became a sharper kink. Although I couldn’t see any visible fuel residue on the outside of the line, the rubber was cracked at the kink and I think there may have been enough deterioration to cause an air leak overnight. Of course the fuel supply would have been a bit marginal anyway due to the kink in the line and that, coupled with a slight air leak, must have combined to create the hard starting condition.
Interestingly (to me at least), soon after I started driving my ’83, 6. 2L Chevy in the mid-eighties I had bad problems when I was using the driver’s side tank. It was even more gutless than when using the passenger side tank (and that was pretty weak). It would pop off the return line at the injector pump and spray fuel all over everything. I was pulling my 31' Airstream, headed for the Colorado Rockies from Nebraska, but the recurring problem made me opt out of heading into the mountains. A very helpful diesel mechanic in Castle Rock tried to diagnose my problem and wouldn’t charge me much because he couldn’t nail down the problem. I limped through the rest of the trip and then went back home to Grand Island. One day I decided it was time to try to diagnose and repair it myself. Don’t know why I decided to raise the pickup box but I jacked it up one day and found, you guessed it, a kinked return line at the tank! I clipped about an inch off the line and all was well.
Gene
I surmise that over time the line lost some resilience and the slight kink became a sharper kink. Although I couldn’t see any visible fuel residue on the outside of the line, the rubber was cracked at the kink and I think there may have been enough deterioration to cause an air leak overnight. Of course the fuel supply would have been a bit marginal anyway due to the kink in the line and that, coupled with a slight air leak, must have combined to create the hard starting condition.
Interestingly (to me at least), soon after I started driving my ’83, 6. 2L Chevy in the mid-eighties I had bad problems when I was using the driver’s side tank. It was even more gutless than when using the passenger side tank (and that was pretty weak). It would pop off the return line at the injector pump and spray fuel all over everything. I was pulling my 31' Airstream, headed for the Colorado Rockies from Nebraska, but the recurring problem made me opt out of heading into the mountains. A very helpful diesel mechanic in Castle Rock tried to diagnose my problem and wouldn’t charge me much because he couldn’t nail down the problem. I limped through the rest of the trip and then went back home to Grand Island. One day I decided it was time to try to diagnose and repair it myself. Don’t know why I decided to raise the pickup box but I jacked it up one day and found, you guessed it, a kinked return line at the tank! I clipped about an inch off the line and all was well.
Gene
This site is the greatest I must agree! I wish I could get my dad to work on his own truck, then I would have a lot of time to bomb my junk!
. When I started it this morning I was back to the hard starting condition. Running around town it starts normally. It is just the first cold start that gives the problem, exactly as it was five years ago. My next step will be to change the fuel filter as it has been a quite a while since it was last changed (no water in fuel warning, but there could be some crud in the filter I guess). I can't see any evidence of leaks around the fuel heater or the lift pump area. Hope it is not too hard to trace since I've got a trip to North Idaho planned in about ten days.
