Help! Injector return nozzles off-center - PeachParts Mercedes-Benz Forum

Diesel Dan · #1 10-11-2007, 10:18 PM

What am I doing wrong? I just replaced my injector nozzles and am now putting the injectors back in the engine, with new heat shields, and when I tighten them down, instead of the return nozzles lining up parallel with the row of cylinders, they are about 90 degrees off. They are not all identical, but pretty close.

What's going on here? I'm pretty sure I put the injectors back together properly. I paid attention to how they came apart, and there is really only one way all those pieces can fit back together.

Any ideas?

TMAllison · #2 10-11-2007, 10:56 PM

What torque did you use for the inj body?

What about for the inj when you reinstalled it?

P.E.Haiges · #3 10-11-2007, 11:15 PM

Diesel Dan,

It caused by tolerence differences. No problem because the hoses used to connect the nipples are flexible.

It may look nicer to have them all lined up but it is mechanically insignificant.

Did U but everything back in the same holes?

P E H

Diesel Dan · #4 10-11-2007, 11:27 PM

Quote:

Originally Posted by TMAllison

What torque did you use for the inj body?

What about for the inj when you reinstalled it?

55 foot pounds for each. Well actually, the injector body itself I just had to wing it, because my socket wasn't deep enough to get on there. I just had to use my "mechanic's intuition" on that one. I probably got within 5 or 10 foot pounds accuracy.

But anyway, there is no way I could under- or over- torque it enough to offset it by 90 degrees. Once you hit resistance, there is not much more movement.

pawoSD · #5 10-12-2007, 12:09 AM

None of mine are lined up either....they are all just a bit different in their threads. Just attach the braided return hoses and forget about it, nothing is wrong with it.

Brian Carlton · #6 10-12-2007, 08:50 AM

Once you remove them and replace the heat shields and/or the prechambers, the reinstallation of the injector is random and there is no possibility of having all the return nipples in the desired horizontal configuration.

The factory must install the prechamber at a specific angle, with a specific injector to have this alignment present during the original build.

Diesel Dan · #7 10-12-2007, 09:35 AM

Thanks for the reassurance guys! That's good news. I do wonder though, what causes the difference, especially since they are fairly uniform in being off by 90 degrees. I wonder if the new nozzle body is slightly longer or shorter, and if this may cause my spring tension, and thus my pop pressure to be altered?

Dan

vstech · #8 10-12-2007, 09:37 AM

it is not the heat shields that are causing the misalignment. it's the fact that you separated the injector bodies, and replaced the nozzels, it is NIGH impossible to get those back to factory specs. like everybody said... don't worry about it, they work fine out of parallel.