has anyone taken injectors apart on this forum?

[319cssb]

So here is what I have done to clean my injectors. I an not saying this is the way it is supposed to be done. I am just describing what I did and what seemed sensible to me.
your experience may vary. I didn't find much info or photo's of how the injector look and come apart and so I decided to share my photo's

First I cleaned the entire injector in 99% alcohol and stuck it in my ultrasonic cleaner on 75 degrees for 20 mins.
then I took the injector out and loosen the two halves a tiny bit and cleaned it for another 20 mins in fresh alcohol solution

then I opened the injector all the way, taking care and paying attention of how the pieces would come apart

here you can see the two halves bottom part with nozzle nut, heat shield, pintle nozzle, intermediate plate, pressure spindle and the top part with pressure spring shims and high pressure inlet

here are the parts
from left to right ,heat shield pintle nozzle intermediate plate and pressure spindle

the top half with shims and the pressure spring to the right


Here it took the pintle nozzle further apart and you can see the needle valve.

I stuck those bottom half parts in the ultrasonic cleaner again. and then cleaned them thoroughly with q tips and kim wipes. and put them in the ultrasonic cleaner again.
I used fresh alcohol every time in a plastic quart container with lid.
I then lubed the pieces with Howes diesel lubricant and checked for a smooth fit.

finally I reassembled the injector noting carefully how all the pieces go back inside.
It's pretty straight forward.

 

[dependable]

Cleaning them will probably help a lot, but when you pop test them, if the spray pattern is still not even, you may need to replace nozzles and lap the them in. I have not had to do this on many 6.2s, maybe because they usually do not live that long, but it is a common practice servicing Mercedes OM 616 & 617 diesels, which regularly go for 300K miles. They use basically the same Bosch injectors as the 6.2 & 6.5, with a different nozzle.

 

[319cssb]

I have not noticed any wear and yes youre right these injectors for the most part have under 100k miles on them. Its crud and carbon that collects and make these work less efficient. You noticed i have not touched the shims. I noticed a bit of a positive change, but i want to changr out the return lines before moving on to another injector.

 

[319cssb]

What holds the leak off ports on the injector. Can they come lose? Do they screw in?

 

[gringeltaube]

I think they are just press-fitted, not screwed-in. I have never had one come loose; not even after slightly bending them (accidentally).

 

[319cssb]

I think one may be lose. I got new return lines and there still is a slight leak from the hose i think it may be the fitting. Maybe I pulled it out some when i messed aroumd with pulling the old hose off. Not sure. Maybe i bent it some when i used a 30mm deep socket on it.

 

[Jake59]

Sorry, just catching up now.
The leak off tubes are press fitted in these Bosch injectors.
You can gently try to tap it back in using a brass driver and going very carefully.

What is the torque to tighten the two halves of the injector housing? 90FtLbs?

Jake

 

[gringeltaube]

What is the torque to tighten the two halves of the injector housing? 90FtLbs?

70Nm or 50 Ft Lbs

 

[cruzer747]

70Nm or 50 Ft Lbs

torque on the bodies is 90#, injectors to the head is 50#

not sure if it is proper to list another forum but I had this same question a while back.

 

[cruzer747]

also, yes.... not worth tinkering with without making/buying a pop tester. Whether cleaning or replacing nozzles I will say that I have enough firsthand experience (pop testing a handfull of different sets of bosch and rebuilding with a chinese nozzle set and testing after 20k, the chinese nozzles are not garbage. Bosch will likely be coming from india these days. My 20k china nozzles are putting off a better pattern than my low mileage bosch set. Go figure, just dont call the chinese junk. Lastly while you can get better spray patterns and retune pop pressure to whatever you are after with some shimming it is usually best to just swap out the nozzle assemblies as I am not the only person that has wasted plenty of time trying.

looks like an oldish thread, I wonder if OP can chime back in to where they are at with this project.

 

[Jake59]

Hi Cruzer,

Yes, I have a diesel injector tester and will be checking spray patterns and leak testing each one.

Cheers,
Jake

 

[gringeltaube]

.... not sure if it is proper to list another forum but I had this same question a while back.

Not a problem to do so.

I know you are referring to this discussion from two years ago, at the Dieselplace.
Specifically posts #17 to #23 get to show that there is no Bible with a straight answer to this....
Read https://www.dieselplace.com/threads/injecter-nozzle-housing-torque.945690/post-9482594 ... and down.


BTW, I've always torqued mine to 50 FtLbs and had no leakers, so far.

 

[cruzer747]

Not a problem to do so.

I know you are referring to this discussion from two years ago, at the Dieselplace.
Specifically posts #17 to #23 get to show that there is no Bible with a straight answer to this....
Read https://www.dieselplace.com/threads/injecter-nozzle-housing-torque.945690/post-9482594 ... and down.


BTW, I've always torqued mine to 50 FtLbs and had no leakers, so far.

Exactly, and post #12 is where I had all of my injector housings leak as I did not lap the mating surface....

I guess if everything is perfect then #50 can work tighter is tighter and also effects pop pressure(cant remember if I have verified this myself). On a 6.2na I wouldnt worry so much about avoiding a leaker but on the 6.5t it is so hard to get into the turbo side that having the insurance of having the extra torque to avoid a redo is optional.

edit-also this thread has some interesting info as well. To be clear the non turbos will like to be set at a lower pop pressure so make sure you have the proper specs for your IP when rebuilding and shimming injectors. https://www.dieselplace.com/threads/injector-testing-rebuilding-and-pop-pressure-adjustment.981938/

 

[Rutjes]

Just came across this info, might be of use to you guys.

Injector Numbers
BOSCH
New #-----------Body #----Reman----Tip-----Pressure---Application
0432217081....0430211051...NA50X...0SD248....126 bar......6.2L 1982
???????????.....0430211058...NA52X...0SD253....126 bar......6.2L Long body
0432217092....0430211054...NA51X...0SD253....126 bar......6.2L Short body
0432217229....0430211054....??????...0SD304....126 bar......6.5L N.A.
0432217251....0430211054....??????...0SD304....142 bar......6.5L Turbo
0432217255....0430211054....??????...0SD311....150 bar......6.5L TD Marine
0432217275....0430211097....??????...OSD304....126 bar......6.5L N.A.
0432217276....0430211097....NA56X...0SD304....142 bar......6.5L Turbo

"bar" is equal to 1 atmosphere - multiply 14.7psia by the number on each line to determine actual injection pressure

Delphi Injectors
6703803---6.5 T.D.
6703802---6.5 N.A.
6703801---6.2 "Van" Short fine thread
6704001---6.2 Long fine thread.

Standyne Injectors (New)
37818 10233973 6.5L T.D. same as 0432217276 6703803
38272 10233972 6.5L N.A. same as 0432217275 6703802

* Info has not been verified but is believed to be accurate till somebody proves otherwise.

 

[Jake59]

Thank you Rutjes,

Good to know and confusing at the same time... my 1985 M1009 has Injector Body Bosch 0430211058 with Nozzle tip 0SD248...
Not sure what to think about that...

Also, I started removing my injectors one by one and giving them a thorough inspection and cleaning.
The first two I torqued together with 90FtLbs or 120Nm. That really felt like a lot, specially as I noticed that breaking the injector body loose took only about 50-60Nm on each and every one.
As this had me worried somewhat, I decided to try and get an exclusive answer directly from Bosch on the subject.

Thus I contacted Bosch Classic in Germany and asked their specification for assembling the injector body halves when replacing the nozzle tips (so NOT the torque of the injector in the cylinder head).

Their answer is clear: " Bei den Düsenhaltern der Bau art KC in Größe S wird die Düsenspannmutter mit 6 bis 8 kgm entspricht ca. 60 bis 80 Nm festgezogen."

So 70Nm or 50FtLbs is definitely on the mark and it seems the Dieselplace got it wrong on this point!
I'ld rather go with the information coming directly from Bosch Classic... .

Best,
Jake

 

[Jake59]

Addition to my previous posting: The following information was also provided with the same email from Bosch Classics and which is, come to think of it, all be it obvious, nevertheless relevant to all of us here:

" Beachten Sie bitte, dass neue Düsen auf einem Düsenprüfgerät eingestellt werden müssen. "

Translated: Please keep in mind that new nozzles must be adjusted (shimmed) on an Injector Nozzle Pressure Tester (to set the correct opening pressure)

I found some information on another website, which may be useful for 6.2 and 6.5 liter engine owners. this information is from an old Mercedes owner, but the injectors are just about the same design and model as from the GM 6.2 and 6.5 liter. Perhaps someone here has access to information to confirm/deny.

"Den Druck verstellt man, indem man dickere oder dünnere Plättchen einlegt (pro 0,05mm dicker werden es etwa 3 Bar mehr, so etwa).
Dann feste wieder zuschrauben und im Prüfgerät testen.
Diese Plättchen gibt es von 0,8 bis 1,96 mm.
Die Drücke sollten im Gesamtmotor nicht mehr als 5 Bar auseinanderliegen."

Translated:
"The pressure is adjusted by inserting thicker or thinner spacers (for every 0.05mm thicker, opening pressure increases by about 3 bar).
Then reassemble the injector and test the opening pressure on an Injector Tester.
These adjustment spacers come in sizes from 0.8 to 1.96mm thickness.
The pressure difference in between all injectors should not be more than 5 bar apart. "




Below is a list of adjustment spacers, with their nominal thickness and Bosch Part Number (and Merc numbers as well; note that Merc jumps with 0.05mm between spacers vs 0.02mm to 0.04mm for the Bosch spacers).

As mentioned, this list is for Bosch Injectors as used in Mercedes Diesel cars, series 190D or W110 all the way up to 300D W124. These injectors are slightly smaller then the 6.2 (Merc uses wrench size 27mm vs. 30mm on 6.2/6.5), but I believe these adjustment spacers could be the same. (I'll check when I pull my next injector on the right side bank and measure the spacer diameter to see if it is indeed 11.5mm!). The fact that these have a hole in the middle has no influence on their operation.





Added a few pics of my injector tester FYI.

Wanted to post a short video clip on the tester being operated but that does not seem to work for me... ?

Stay safe!

Jake

 

[dependable]

I've cleaned dissasembled and cleaned 6.2 injectors and have rebuilt injectors out of Mercedes (OM-617 engine w turbo), and can confirm they are the same except for above noted thread & nozzle differences.

The nozzles on the Mercedes injectors showed visible pitting, both cars had over 200K miles on them. None of the 6.2 injectors I have cleaned have shown enough wear to need new nozzles, but cleaning did improve spray pattern.