i changed my injector tips lastnight and evrything went fine until i was done. there was a leak on the number 4 cyl injector line right where it screws into the head. its not leaking out of the line but around the nut that screws into the head. what could be wrong. the threads are not cross threaded and i tightened it as tight as i could get it. has anyone had this problem and if so what did they do to fix it.

 

The only thing I can think of, you'll have to use some fine 800 grit emory cloth to smooth out the part of the injector line that fits into the connector tube.

 

What did you use for installation instructions? Following the often-cited Diesel Dynamics installation sheet, the injectors should not be final-torqued before the cross tubes are tightened. These components need to be able to conform to achieve a tight seat. By following these instructions, I've never had a problem with leakage.

Rusty

 

i did torque the injector down before i tightened the line. and i did that on everyone but i only have one leaking.

 

One's enough, isn't it?

Rusty

 

yes it was running like it had a cam in it at idle. but it ran fine when i was going.

 

If you didn't need a new crosstube, you do now.

 

ok so you are saying in order to fix the problem i will have to pull the injector and tube and get a new tube. thats the only way.

 

anyone have the cummins number on the tubes

 

could just be the o-ring on the flow tube

 

Did you replace the crossover tubes and o-rings when changing tips? If you didn't, did you at least check them both for damage, cuts, twisting, roughness, etc? Maybe overtightened them too much? Check and clean the mating surfaces from fuel lines(male to female) with fine emery paper to remove any rust, corrosion, nicks etc ONLY AND NOT METAL, so mating surfaces are clean and smooth. Clean off any dust etc from both mating surfaces carefully, before reinstalling. Ideally this SHOULD be all done on the work bench, to ensure cleanliness. Retighten so it's tight, but not excessively.

If it doesn't stop it, then you'll have to remove and inspect/replace bad crossover tubes(if one's bad change them all), and replace all o-rings.

 

Torque specs on the head end are 28ft lbs and only 18ft lbs at the IP end of the fuel lines. So making them as tight as you can probably damaged the tube.

 

i had the same problems on 2, 4, and 6. i also tried to tignten them as tight as i could get them. That obvisouly didnt fix it so i pulled the flow tubes and teh o rings were bad. i didnt have any at the time so i cleaned the tube off and stuck it back in. No problems so far! However, i am looking for new ones.....

 

well the problem was when i pulled the tube out with pliers i scratched the tube a little and the line wasn't seating. so i sanded it down alittle and fixed the problem.

 

Glad you got it fixed.