Does anyone know if there's an adjustment screw for the injector pump on this model? Any help is appreciated.

 

VIN?

 

VIN is 11511010307721. Actually now that I look it's a 1973. Kind of new to all this.

 

i haven't seen it before but... maybe it's the #28?

[IMG]local://upfiles/1/28A9513E71F047FB90DF2AD6689D83D7.jpg[/IMG]

 

maybe the adjustment is done by replacing the spacer washer (item #38). that will change the tension of the diagprahm.

 

Thanks for the help! The diagram is fairly close but not exact. There is a nameplate on the side of the pump:

Bosch
Made in Germany
22824813
PEC4M 55C320 R347
D400 114 045

That is the best look I can get at it. Do you know if any Mercedes have injection pump adjustments by screw, or is it a more complex method? Thanks again.

 

Okay, I found a picture of the pump I've got. It is showing the backside of the pump. Basically, take the diagram you provided and turn it around 180 degrees. The arrow is pointing to what I'm thinking is an adjustment screw. Any thoughts?


[IMG]local://upfiles/6735/70C309668EBC4CF49702915337CE81EA.jpg[/IMG]

 

the later one after that have. it's on the back. there is a lock nut and a screw-in plunger.

earlier than that, i think they just adjust the idle speed via linkage.

 

i think we need some help here

i really can't be sure too. hope some members got this knowledge on which to.

 

I didn't think there'd be a prayer that my knowledge, based on working from M-B-manuals on a 1959 180-D. would be relevant, but your illustrations depict injection pumps that do resemble the one I've worked on, so here goes:

First of all, why do you want to adjust your pump? Is it low power output, excessive smoke, or what? In either case, you need to know firstoff whether the vacuum diaphragm is any good -- it controls injection volume. Mine was leather, and it died on the road, and the only way I could regulate the engine speed was by turning the dashboard control handle partially toward the "off" position (later cars use a pull-type control).

My manual gives a procedure for checking the diaphragm:

Remove the cap over the (feed volume) control rod -- at opposite end of injection pump from the vacuum diaphragm. Disconnect vacuum line at diaphragm housing. Press with adjusting lever the control rod fully in direction "STOP" (inward). Seal the vacuum connector with one finger. Then release the adjusting lever and watch the control rod. It should come back out only a short distance under spring tension and then stop. If it comes out all the way, the diaphragm is shot. Pull your finger off the vacuum fitting to find out what "all the way" means. If the rod didn't come out any further when you did that -- bad diaphragm. The diaphragm housing comes off with four screws; then disengage the diaphragm fixing bolt and remove the diaphragm. On mine, the problem was obvious at that point.

If you really do just need to adjust something, the obvious thing to fiddle is the full-stop adjustment, a slotted screw with lock-nut directly below the diaphragm housing. The manual suggests adjusting it if the engine smokes heavily and consumes too much fuel. It also gives specs for measuring the control rod travel, but these are probably 'way specific for different engines.

Glueck auf!

--Allen Moore