Hey all,

I just bought a 1973 220D with either 91k or 191k miles. he car runs but was smoking black at idle as well as while driving. It's not terribly bad but I would like to try and fix the problem if possible.

I checked the easy things first; throttle linkage, vacuum pump for oil, re-lashed valves, checked gov on IP for leakage by applying vacuum and it held.

I decided to check the IP timing as to maybe this was causing my smoking problem.

The problem is, I can't time it. I followed the instructions for drip timing located here PeachPartsWiki: How to Set IP Timing via the Drip Tube Method

I fashioned a drip tube out of a spare set of lines I found in the trunk.

I removed the pump element of #1 cyl. Removed spring and delivery valve and re-installed the element then connected the drip tube.

Turned the engine by by the damper to 24 degrees BTDC.

When I pump the IP, I get no fluid out of the drip tube. In fact, regardless of where the crank is, I never get fluid out of the drip tube.

If I loosen the pump element a tad, and pump the IP again, I will get a steady stream of fluid. Even with the slightest amount of torque on the pump element, it will not squirt.

The other pump elements do the same thing.


My question is; is it possible that I have the wrong pump elements for this bosch pump?

I also noticed there is no crush washer installed, there was only a O-ring on the pump element for sealing. Could the lack of a crush washer cause this to happen?

Thanks for your help, I refuse to let this thing beat me!

Did you remember to hold the stop/stop lever all the way back to ensure the rack is pushed forward fully?

You can disconnect the linkage right at the pump and use a zip tie to hold it back while you test.

Ok, I got it figured out. It seems like I had to disconnect the rubber return hose ( I think that's what it is) that goes from IP to the top of the fuel filter housing.

And there were crush gaskets after all, I just couldn't see them installed.

After timing, the car still smokes black and idles rough with low power.

I am now suspecting fuel nozzles. As I was bleeding the fuel system, I cracked each fuel line at the injector and let some fuel squirt out. Each cylinder I did this with would cause the engine to idle worsen, almost stalling. Except #3 cylinder. When I loosen the #3 fuel line at the injector, the engine idle makes no change which leads me to believe that it's a nozzle problem, maybe not getting a good spray pattern.

I also need to do a compression test as soon as I can find a kit that will have the right fittings.

I have used this compression tester on my w115.
12 Piece Diesel Engine Compression Tester
It is not a quality device, but is good enough for getting a general sense of overall engine health.

I would recommend you do the compression test sooner, rather than later. It is fairly cheap and provides key information to solving your problem.

__________________
1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).

Thanks Shortsguy1. That's what I was looking for. Ordered.