So my truck has been a blue smoke mosquito duster since I bought it. Has 129k and I've only put about 200 miles on it so far. Blue smoke started to clear up after it was nice and warm and one good acceleration to about 2800 RPM.

Blue smoke also liked to come back at idle even when warm. I noticed it was using a bit of oil and I just changed the fuel filter. Looked like black oil in the bottom of the bowl and it turned a paper towel black when I wiped it out.

So I've got a set of orings for 8 injectors coming. Do you all usually just replace orings for injectors all at the same time? Or is there is a way to pinpoint which one has a lower oring failure? Am I looking at a 3-4hr job?

Thanks, Ben

 

I would do all.it is impossible to pinpoint really. You are on the correct path.

 

Cool, thanks. Good to hear. I'm really loving this truck and gradually the list of neglected items is dwindling down.

 

It's a bit closer to a 5 hour job when you include the R&R of the valve covers and you've never done it before. It's not bad.

1) Only use Alliant O-rings. If you bought aftermarket, send them back and order Alliant from dieselorings.com or Riff-Raff Diesel.

2) Wipe out each injector cup and visually verify that there aren't any cracks in them.

3) Lubricate the new O-rings prior to re-installing the injector. Use hand force only to press the injector down in until you feel it seat in the cup. This ensures that you don't pinch the O-rings. Then you can tap it in lightly until the hold-down bolt will engage. Tighten it from there.

4) Top off the HPOP reservoir via the plug on the top. It will take quite a bit of cranking to start it the first time. You need to drive it for about 60 miles after finishing the job to get all the air out of the high pressure oil passages and get it to run right.

5) Save the beer for the end of the day.

6) Now's a good time check your UVCH for wear, shorts, etc. Do the quarter trick as preventative maintenance if it's applicable to your truck (I don't believe it is) https://www.youtube.com/watch?v=GHwjEfJtM_g#t=567.

7) Test and replace your glow plugs while you have the valve covers off.

 

Thanks for the tips.

Alliant is what I got coming. PO supposedly just put all new glowplugs in and resistance looks good through the VC gaskets. Had one replacement external harness that was just twisted together and black taped into the engine harness. Cut fresh ends, soldered and shrink fit those, and it seems to start quicker now...

I'm hoping the cups look good. Are cracks pretty easy to spot? I saw you may see coolant residue at the injector tip if bad?

This beast seems to run pretty good, just blowing the blue smoke. Did seem to take a while to start but that seems better now that I soldered the harness. I also found the short hose to the fuel pump was a little long and had a kink.

 

Ok, so I got the injectors out last night and I think they look pretty good for the most part. Cups also look good. No sign of coolant or cracks in there. A couple of the hold downs seemed looser than others.

Some of the tips have light carbon deposits and others seem like they may almost wipe off. Some have caramel like deposit past the copper washers, and some have brownish/blackish near the middle (green) o-rings.

What can some of you experienced guys can tell me about the deposits and conditions of the injectors? Truck supposedly is a 129k truck...

I didn't see any distinct torn o-rings but they seem pretty hard and not too thick anymore. I guess I'm asking is which injectors do you think were leaking?

Also, what are preferred techniques for cleaning out the cups and decarbon the tips?

 

Those are either the original o-rings or aftermarket. The Alliant o-rings are now colored pink, orange, etc.

Replace all of them. My bet is that they're just old and worn out. Pinpointing a specific bad one might be tough.

 

I am curious about the green as well.I just pulled mine at 334000 and they are green middles. I can not believe mine are original but I have talked with all but one previous owner and none did any injector work.

 

Do you guys think the blackish deposit on the bottom of my middle o-rings (greenish ones) is evidence of HP oil breaking into the fuel side?

Just curious about the visual cues as I have never read injectors before.

 

Now that you point that out I have a feeling you might be on to something there.