Engine/Transmission (1998.5 - 2002) Injectors won't stop leaking!!! Thread sealant??

[leathermaneod]

Hi everyone,

My story is a very long one so I'm just going to cut the the important part. I recently had my local diesel shop pull my vp44 to replace my tappet cover gasket. After I got it back I had fuel lines leaking where they enter the head. I took it back to the shop and after about three or four different times and a couple new fuel lines and delivery tubes, their solution was to put thread sealant on the ones that wouldn't stop leaking. IS THIS THE RIGHT ANSWER??? It seems just dead wrong to me. I am seriously thinking about tearing them apart myself and taking some scotch bright or sandpaper to the lines and tubes and just keep at it till I get it fixed. The one mechanics explanation for using the thread sealant was that because my engine is old(250,000 miles), fuel is seeping through the threads/head. But there shouldn't be fuel at the threads should there??? shouldn't the line and tube be sealing together?? and yes the did replace the o rings on the tubes. please give me some guidance here guys this really has me ****** off!

 

[Gotdsil]

Just as in residential plumbing, if a compression seal fitting is leaking, while dope may "fix" it, the problem is the "dope" who did the work. I can't tell you exactly what's wrong, but time for a new mechanic.

 

[leathermaneod]

Yeah that's kinda what I was thinking. Do you have any experience getting these darn things to stop leaking?

 

[rotohead]

It's been awhile since I had a similar problem. I think part of the problem is when tightening the nut into the head the fuel line can actually turn slightly with the nut and not seat properly on the end of the cross tube. I did what you mentioned with scotch brite pads and then I lightly greased the fuel line where it goes thru the nut. I also had trouble identifying which one's were actually leaking and I used small amount of baby powder under the nut. Hope this helps. I haven't had leaks in 50,000 miles or more.

 

[leathermaneod]

Thanks for the input rotohead, I'll def keep that in mind when I pull them apart.

 

[Gotdsil]

I've never had that problem, but I would suspect either seat is damaged, line or injector, or "nut" got cross threaded, making it seem to be torquing correctly, but not being so. Rotohead's solution also sounds good. I'm just a simple homebuilder, and mechanic by necessity!

 

[BDaugherty]

Inspect the fuel crossover tube and the fuel line. One or both may be deformed. Sometime the sealing suface can be dressed with emory cloth and sometime you need new parts. When the fuel line seats squarely into the crossover tube, it should seal just fine...Remember, it's designed to seal 14,000 plus psi. If it doesn't, fix it. Thread sealant is only hiding the problem. You still have injection pressure being lost to return fuel.

 

[JR]

What year is your truck? Early VP44 engines require the crossover tubes to be replaced if/when taken apart. There was an update to the crossover tubes that allows them to be retorqued but if you've got a 98.5 (and I believe some 99s) you probably need new crossover tubes.

http://dodgeram.info/tsb/1998/14-01-98a.htm