leonesm

My injectors had about 180,000 miles and I was beginning to get a light haze at idle as well as my oil level slowly rising. I couldn't be without the truck so I purchased a new set of injectors with 60 hp nozzles from Industrial Injection.

I put the new injectors in on Sunday following the instructions from DDP's website as well as another set of instructions I found posted here. Long story short, when I finished the truck idled fine and ran but I was losing rail pressure and my fuel level was rising.

I didn't replace the connector tubes (that had 282K) the first time but I figured I would go ahead and do it in case that was contributing to the problem. I went to Cummins and asked for part #3979419. They told me that number was now obsolete and the new number was #4929864. I saw posted on another thread that this new tube is now interchangable with the ones for a 6.7l truck.

I opened it up and think that somehow I didn't get an injector seated completely and that was causing my initial issues. I went through the entire install again, torquing everything to spec and installed the new connector tubes. I made sure the injectors popped into place as well as the connector tubes and followed the correct torque sequence. I checked and rechecked the torque on everything. When I went to crank the truck it was very hard to get started and it would run and maintain rail pressure above 1200 rpm but would die at any rpm below that. I tried to crank it a few more times and had the same results. The only thing different from the previous install was these new connector tubes.

I removed the fuel rail again and pulled out the new connector tubes and replaced them with the old ones. I didn't remove the rocker or loosen the injector this time, just popped the new tubes in and made sure they "clicked" into place. Now the truck runs fine, rail pressure is good and my power is where it should be.

Has anyone else installed these new crossover tubes? They're made differently than the old ones and have a different tip design. I don't know what was happening, but I'm going to return them to Cummins if I can. I see where a lot of people have changed the connector tubes but not with the new part. Just curious to see if anyone else had a different perspective of what was happening.

astep577

i just finished putting everything back together after swapping my injectors tonight...or last night should i say.
anyways, cummins dealer sold me those tubes as well, now i have no start. need to find old style ones for tomorrow i guess and try again

leonesm

I ended up leaving my originals in the truck and returning the new ones. I even had Jeff Garmon look at it and he told me something wasn't right with the "new" connector tubes. Not sure if I had one that was bad or if they really aren't interchangeable, but the set I had wouldn't work for me.

soulezoo

I've not worked with the new tubes, but the conditions you describe point to a faulty seal, or leakage, within the CR system. The injectors won't fire unless the ECU sees a minimum pressure level built up and a leak will compromise that obviously.

Now Cummins does recommend replacement of the tubes at each injector removal but that is overkill. A quick refinish of the tip of an otherwise good condition tube is all that is really needed.

astep577

i already had some old style in the mail and they just arrived. when i pulled the new style tubes out, i found some slight markings where it looked like they didn't seat correctly. i pulled those specific injectors and there are some slight markings where that occurred but i don't think it will interfere with a good seal.
time to put the new "old style" ones in and hope for the best!

dryheat

I installed a set of the new style tubes about six weeks ago with stock injectors. So far so good. Maybe it was just beginners luck.

banyon

When my buddy replaced his injectors the parts man at cummins told him to replace his tubes. When I replaced mine, I walked back in the shop & asked the teck. He said on the later 5.9's to just replace the o rings unless you see pitting or rust. So far so good on mine.

Spooler

Yes, the new tubes are actually the 6.7 ones. I inspected my tubes and I had to replace one. So I did with the new 6.7 tube. No issues.

06RAM2500

Found these on Ebay. Had to replace two of them due to a leak.

http://www.ebay.com/itm/120631939295...84.m1497.l2649

astep577

well i pulled the tubes and injectors, inspected everything, and used the old style oned to put everything back together for the second time and the truck fired right up. i don't know if it was me or the new style tubes, but something wasn't right. maybe they have a different toque spec??