HELP! '75 240D Injectors - PeachParts Mercedes-Benz Forum

Fisherman · #1 07-15-2002, 04:52 PM

I'm back...
I am taking a trip tomorrow and thought I'd attend to some minor maintenence and apparently created a problem.
I replaced the injector bypass fuel lines (3 mm) and when I started the car back up it is now leaking just above the injector nut (i.e. 22mm). In the attached image it is the area with the writing stamped on it ("REMAN for ..."). I can see it bubbling out around the lower edge of this area which is right on top of the 22 mm nut. Can you tighten the "top" section of the injector holder (the part stamped with the 752 or could be 782 in the pic) that appears to go into the "actual" holder (22 mm nut section)? It appears to have a fitting that would accept a wrench (not a hex head as you can see) but I cannot find any reference to this part in my cd manual.

Could I have cracked this section of the injector holder somehow when refitting the new hoses to the nipples or pulling the old hoses off?

I'm at a loss here and need to be ready to hit the road tomorrow for a 1100 mile trip.

Thanks in advance for your help.

dabenz · #2 07-15-2002, 07:25 PM

Try this:

http://www.boschusa.com/AutoParts/DieselParts/Injectors/#

Shows the threads about half way down. Pretty unusual to get a leak there, but if you're going to lose out on a trip, then maybe worth a try. Loosen up the fuel delivery pipe first, then snug collar while holding the nozzle holder body (bottom "nut").

Just a suggestion. I've never done it.

Fisherman · #3 07-15-2002, 08:21 PM

Thanks dabenz.
Another thought struck me while looking at the cutaway on the Bosch site.
Could it be that I pulled the return tubes part way out when I was pulling the old lines? They were really stuck on there and I had to use pliers and a razor knife to score the outer skin?

Anyone know if these tubes are just tapped into a tapered hole? Maybe tapping on tyhe tube ends will seal them back up. It doesn't appear to be leaking from the tubes but then I had very small leaks before and some of the hoses that I replaced appeared to be damp so I assumed it was the hoses that were leaking. Maybe it was the injector holders all along?

dabenz · #4 07-15-2002, 10:07 PM

Can't help there. Well, maybe try a bit of Permatex on the nipple behind the wide part, if you think the return lines aren't sealing. The drill for me these days is to pull the nozzle holders and take to the experts at the injector shop. That web site has a listing of shops/service centers. Usually the grungier the outside of the building and the older the tech the better quality work they do. The shop or your CD will show the parts that have to be replaced every time.

Fisherman · #5 07-16-2002, 06:42 PM

Well I went ahead and made the trip and it appears that the leak may have just been residual diesel from changing the hoses. Guess I kind of panicked there...

The car sure runs nice at sea level instead of 3200 feet where I live.
Odd thing though that the smoking problem that I have at home has completely disappeared. No smoke and more power...

I have a pneumatic goverrner on the car with no apparent alda unless that is what the vacuum line to the back of the IP is for?
Does anyone know how these IPs work in relation to altitude? Could I have a bad diaphram in the back of the IP that is not correcting for altitude now?

Any help anyone can lend would be mucho appreciated. I hate not knowing how something works and the manual does not cover the IP at all ("other than take it out and have it serviced")

dabenz · #6 07-16-2002, 09:54 PM

No smoke and more power probably means you finally cleaned it out with the road trip.

Altitude adjustor: try "Lots of smoke - Altitude?" from the search. Can't figure out how to post a link to it.

Will look at my CD to see when the altitude adjustor came in. If you don't have one then you may need to adjust pump.

dabenz · #7 07-16-2002, 10:19 PM

From the 114/115 CD I bought from this site: Mechanical altitude adjustment for 617 engine from 1975-1976, automatic adjustment for 616/617 engine from 1977 forward (the CD does some W123 stuff).

I do know dabenz doesn't have it. Live at 850ft and smoke a bit more than usual at 5000 ft and up, but at 36mpg average with satisfactory power I don't worry about it.

If you're happy with fuel mileage, smoke, and power then it may not be something for you to worry about, either.

Fisherman · #8 07-17-2002, 01:04 PM

Thanks for the input dabenz.

I have the same cd and the problem is that it really doesn't cover the 616 engine circa 1975 all that well. I will probably try and call the local dealership and see if they can lend any info concerning the altitude adjustment on my IP but in the past they havce seemed less than knowlegable on the 115/616 combination.

When I go through the survey for the IP on the CD my IP part number does not even come up. It's fairly close but not exact to what the CD lists so I'm actually beginning to wonder if this IP is not the stock one that came on this motor? The only info on the CD that I cna locate for this IP is the start of delivery processes but nothing of any real relevance concerning operation and function. For those with a similar year/model I'll post what I find out after doing my research.