Archived Injector install, now oil???

[Matthug]

I installed 300 injectors today. Made sure I cleaned out where the copper washer seats down in the bore, all the injector nuts are torqued, but the injectors I got didn't have dust seals on top on the injector nut. I installed them anyway figuring I would get to the dealer monday and pick up a set. Well now I have oil coming up through the injector nut! Well I don't think this dust seal is meant to hold out engine oil, but maybe I'm wrong? Nothing comes out when it's sitting there idling or no load revving, it only comes out when it's under load and WOT. My bro (diesel mechanic) tells me to wait it out for a day and drive lightly, wait and see if everything seals up.

I cannot audibly hear any miss or anything like a compression leak. But like I said nothing comes out idling just WOT full load. Any ideas? Wait?

Thanks in advance.

 

[K5IP]

I had a similar problem when changing the injectors in my 95. Even though I used nome new copper washers, they were not a cummins product. I ended up removing the injectiors (three of them) and dressing the copper washers against a flat file until all imperfections were removed. They I retorqued the injectors to factory specs and they sealed ok.

Do not over torque, this can cause the nozzle tips to become deformed causing leakage. Leaking can also occur where the nozzles are mated with the injector body. If you have aftermarket injectors, there might be some concern here too.

The dust seals are there primarily to keep water from getting down into the injector hold down nut causing rust problems. They will not have any effect of leakage.

Rog

 

[Matthug]

I bought Bosch 300 injectors from city diesel. I did over torque them, didn't have specs with me at the time down at the garage and for some reason I had 70 ft/lbs stuck in my head. I figured they needed to be tight. Come home, read it's only supposed to be 44. So I will go ahead and take them all back out, re-clean surfaces then torque to proper specs. I hope this works!

 

[Signal73]

Maybe over squished them deforming them? I found city diesels install kit for the 12V injectors I got from them was junk. half of the return line washers were the wrong size I had to wind up reusing some of my factory ones because the holes for the banjo's were too big. I think the name diapco sticks in my head when I try to recall the brand name of the kit.

 

[Matthug]

Deformed what? Just the washer or the entire injector???

 

[Signal73]

If anything at all Id probably say the soft copper injector washer at the bottom of the bore.

 

[Matthug]

Well i took the injectors out, cleaned out the bottom of the injector bore better this time and cleaned up the copper washer. The copper washers looked well squished down but I didn't have replacements. So I put it back together nice and clean this time and torqued to 50 ft/lb. It leaks a lot less than before and seems to run better cold now. So I think some new washers will fix things up. Thanks for your help guys.