Had my injectors tested. Need input. - Page 3 - PeachParts Mercedes-Benz Forum

oldnavy · #31 06-11-2004, 11:00 PM

So what is the PSI on the injectors and IP on a 240D? Just curious is all.

I know it's no where near my Jetta or the new '04 VW PD's 29,000 psi pump injectors. I bet those cars are going to have some major problems with US dirty fuel. OEM VW fuel filter is 10 micron nominal, 20 micron absolute.

coachgeo · #32 06-12-2004, 12:17 AM

Quote:

Originally posted by oldnavy
So what is the PSI on the injectors and IP on a 240D? Just curious is all.

... OEM VW fuel filter is 10 micron nominal, 20 micron absolute.

My understanding is that the 20 something year old MB's main fuel filter was 5 micron 10 absolute. I may be wrong. Im sure others will correct me if so.

Also I beleave the US diesel standards change to Eurospec or close to it in 2006

coachgeo · #33 06-12-2004, 12:22 AM

BTW... had an interesting conversation with a diesel guy. Apparently the DI design was available way back but the decision was to NOT use it in MB engines but go with IDI (and other company's made simular decisions Im sure) because it is not as efficent and makes for a noiser engine. Lot of redesign went into the DI injectors (on topic point), coolant passages, engine mounts, insulations on the bodys etc. to quite down the DI engines of today. They are showing to have less life than the IDI design too..... but.... better emmisions. Not complaining tooo much. I guess our air is worth it.

oldnavy · #34 06-12-2004, 12:48 AM

What makes the DI diesel pretty much what it is today is the computer contol of the IP. With the VAG-COM program I can actually very the timing of the IP and IQ with my laptop. Adjusting the IQ on the VW TDI can really quite down or smooth out an engine or give it more zip.

I've had one MB tech tell me the filter on the old diesel 123's were 5 micron and that the new MB E320 CDI cars have 2 micron filter's.

I'd love to have a new Chrysler 300C with a 6 cyl CDI engine, that would be the best of both worlds, looks and diesel.

DieselAddict · #35 07-04-2004, 02:41 PM

I finally got the injector tester and much to my surprise it does work with 603 injectors. I already installed new nozzles in all of them and was going to install them today, but now I gotta test them first. Hopefully these new nozzles (made in Turkey) are good.

DieselAddict · #36 07-05-2004, 12:13 AM

I just finished testing my injectors. It appears that those Turkish nozzles are pieces of s**t. I got a variation of up to 18 bar and one had mediocre spray pattern and one had a really bad spray pattern. I guess I'll be reinstalling at least some of the original German nozzles.

I have a few questions and I'm hoping someone who knows can answer. Is the huge variation of pop pressure likely due to the shims or springs that are used or could it be the nozzles? How's that knob on the tester used? It appears that it restricts flow when it's fully closed so I had it a few turns open during the testing. What's a good source for the various sizes of shims that I need to balance my injectors? Finally, if my German nozzles turn out to be too worn, is my only option to just keep exchanging these Turkish or Indian nozzles until I find good ones?

jbaj007 · #37 07-05-2004, 02:08 AM

"Pop" pressure is determined by shim and spring, primarily. Shims are easy to change out and swap around, so they're what is used to adjust pressure. For every 0.05 mm. increase in shim thickness you get about 3 bar pressure increase.

Spray pattern?... you're on your own.

I'm going to try "lapping" the pintle to the nozzle with some very fine diamond paste to resurrect a couple of old nozzles (I've got a bunch). I'll see if there is any future in it.

Source of shim assortment source in the U.S.?.....the kindness of strangers and the wreckers is all I've been able to rely on.

The break pressure for the injectors in a 240D (someone's previous question) is 115-125 bar new; 100 bar used, according to the 1985 TDM.

DieselAddict · #38 07-05-2004, 05:01 AM

One thing that I noticed about these new nozzles is that they vary significantly in pintle sliding friction. You're right about using shims to adjust pop pressure, but I'm also thinking that this varying friction could be messing up the pop pressures, and probably the spray pattern too. What do you think?

That's too bad about the availability of shims. I'll try the local diesel injection shop but I don't expect much. First I'll probably try reinstalling some of the old nozzles and maybe swapping a few shims around, though they all look the same and are probably the same size.

rwthomas1 · #39 07-05-2004, 03:14 PM

Nobody ever answered the question: Is TomJ the Colorado Gold guy? Anybody use these injectors yet? They look nice, price is right, but...... RT

DieselAddict · #40 07-05-2004, 03:52 PM

I think TomJ is the Colorado guy. When I asked why this Colorado guy has the Indian nozzles pictured on his site, TomJ replied that that was before he knew they were crap. I would like TomJ to reply again to this thread, especially as to where to get those shims and how he deals with these bad nozzles.

TomJ · #41 07-06-2004, 10:45 AM

Quote:

Originally posted by DieselAddict
I think TomJ is the Colorado guy. When I asked why this Colorado guy has the Indian nozzles pictured on his site, TomJ replied that that was before he knew they were crap. I would like TomJ to reply again to this thread, especially as to where to get those shims and how he deals with these bad nozzles.

Hey, sorry about not getting back till now, spent the weekend with a basket case engine I had to re-assy (without all the parts/hardware) and haul up from the basement and drop into the truck it was out of. Shop that rebuilt it took it back apart after it blew up in 500 miles and threw everything in carboard boxes (not everything) and threw (literally) into the bed. What a clusterhump!

Anyway, more and more are sending me their "NEW" (rebuilt) injectors 'cause they're not working right. Ten out of ten times so far, they are because of these nozzles. Problem is, I have no source for German nozzles anymore. If I order nozzles, it's hit or miss with getting anything other than Indian ones. Last batch I ordered from Rusty were ALL India.

I've pretty much given up on doing injectors. Kamil is getting the last of my "good" (newer, not worn out) German nozzles. I still have some really worn ones that pop and spray good, but I just can't put these into someones injectors and call them rebuilt.

I'll take some close up pics of the differences and try to post. Meanwhile, I'd suggest people keep what they have and just balance them and NOT get rebuilts as the likelyhood is 100% that they will have the India nozzles.

DieselAddict · #42 07-06-2004, 01:40 PM

Hey Tom, thanks for getting back to us. Having already bought these new nozzles and seeing first hand how crappy they are I now share your frustration.

How about those shims? Do you know any good source?

TomJ · #43 07-06-2004, 01:56 PM

Quote:

Originally posted by DieselAddict
Hey Tom, thanks for getting back to us. Having already bought these new nozzles and seeing first hand how crappy they are I now share your frustration.

How about those shims? Do you know any good source?

Had a guy quote on some metric shims in 1mm increments, seemed fairly priced at the time, but I would need to buy 500 at a time. With as few of these that I do now, it's not worth it to me.

A few things you can do; switch and swap springs (they came in various lengths, .865, .870, .875, etc.), upper bodies (measure the depth of the spring recess and swap accordingly, and the poppet/spring seat that goes on top of the nozzle pintle. With all that, you can usually get within +/- 4bar.

I have a stock of all parts and a bunch of shims, with the way it's going with the nozzles, I may just sell my stock and get out of doing them. Will post here first if I decide to do this. Otherwise, the Bosch shops sell the shims, but they're $3 ea in packs of five.

coachgeo · #44 07-06-2004, 02:37 PM

I might be interested in your parts and pieces if you decide to sell them. I very much need a little at home work. I'm looking for ways to stay around the home to better care for my aging folk yet make a little mula. Dad was just in the hospital again and mom is the on that's the most ailing out of the two.

DieselAddict · #45 07-07-2004, 03:19 AM

I tested my old German nozzles tonight and it appears that 4 of them have good spray pattern and 2 have decent pattern. Of the new Turkish nozzles, 4 had good pattern, 1 had decent pattern and 1 had bad pattern, almost a solid stream. So it looks like my 18 year old German nozzles are better than the brand new Turkish ones. Now I just have to decide if I should return all the new nozzles or keep 2 of the good ones to replace the German ones with the "decent" pattern. Any thoughts?

The way I judge the pattern is by looking at the width of the cone. The "decent" ones had a somewhat narrower cone than the "good" ones, but no solid stream like the "bad" one. Is it correct to assume that the wider the cone the better the spray pattern or is there a point of no returns?

Interestingly, the pop pressure does vary with different nozzles. I tested all the old German ones in the same injector and got a variation of up to 14 bar.