W110 W111 W112 Sedan, BENZ AID - COMMON QUESTIONS AND ANSWERS

Hi all,

I've got a 1979 300TD non-turbo that isn't shifting correctly. I'd like to start out with the vaccum system, but can't seem to come up with a schematic.

I've got Kent's transmission tuning manual, but the transmission in the 1979 wagon looks to be different than any of those explicitly described in the manual, and the vacuum schematics in the appendix don't seem to match either.

I've got two questions:

What is (and how do I test) the item labeled "B" in this picture? (I assume it's the VCV)

This 300TD-T has been running on Veg for about 3 years and 12k miles, I have owned it about 5 months. The rebuilt engine has 50k miles in it. Starting two weeks ago, the wife noticed a subtle power loss on hills and more white smoke than usual (this car has burned very clean except at start up). I drove the car last week, and tested it on a few residential hills in the neighborhood. At idle, the engine revs well…on the flats power is OK, but definitely not as strong as a few weeks ago… going up steep hills is impossible.

In doing some routine maintenance on our recently acquired 300TD-T I came across what has been called the "switch over valve" attached to the fire wall, next to brake booster. Both the vacuum line from the turbo and the alda have been disconnected and a short piece of hose connects the two.... a bypass. I understand that this can damage the engine. Is there any test to see if this valve still works before I reassemble the correct way?

Thanks is advance.

Steve

I just replaced my differential mount. Yes, it fixed the rear sag problem!! One of the 4 13mm bolts that hold it into position on the subframe snapped off inside the subframe while removing the old mount. Is there a way to get that piece out of the hollow subframe member so I can replace the bolt (assuming the threaded insert is ok...I suspect it may be rusted, thus the break)? Are bolts 3 enough to hold the mount in place?