Wednesday I made an attempt at replacing the B2 piston in my 84 300TD. The end result is that the car acts the same as it did before the replacement. That being said, the old B2 was in pieces when I took it out...

I guess my question is How does the B2 piston work, Does it push against the b2 band to provide friction...? and when I took it apart there was spring pressure against the b2 cover, is there supposed to be a spring that pushes against that cover to keep the piston toward the inside of the transmission? Or does transmission fluid provide the force? One other question which I wondered about is this: some of the pictures I saw on installing the b2 use a special tool to push the piston/cover into place suggesting that it is a bit of a bugger to drive into place... mine slid right in with very little effort, could it be the wrong part?

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46 WDX Power Wagon

84 300TDT daily driver

Some of these links may help answer your questions.

Transmission:
Transmission:





Have a great day.

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wHunter,
You are probably the best forum member on this site for good links to answering questions (not discounting other member's who also provide good links when appropriate). You are one of the forums indispensable members. Not a bit of idle "pat on the back" in that.

The B1 piston has the heavy springs, did you remove the B2 showed below , if so did you install the band apply pin showed in the picture. The pin applies the band; maybe it did not engage the band. Remove the B2 and insert the pin into the B2 with cold Vaseline to hold it in place, and reinstall it, did you change the B2 bushing and seal. Did you notice if the B2 band was broken /damage when you removed the valve body


.

oops...

The band apply pin is still in my collection of "used parts" and not in it's proper place. That is why it doesent work! I made the assumption that it was a part of the broken B2 piston that I took out, and did not realize that it has another job to do. will try the cold vasaline 'glue' trick..
Thanks for your help. Do you rebuild these transmissions for work, or have you just been playing with them for a while? How about rebuilding the manual transmissions in the 240D's? Is that a tricky job, or fairly standard? I was having visions of swapping a 4speed in to the 300TD.. there is a donor car about 20 miles away that may be able to be had. Also I tell myself that it may boost my mileage, as well as being more predictable about when it is about to go south.
That being said, as I recall, the automatic in the car has been shifting slightly harsher than it used to. (and the vacume supply has been disconected since before I owned it) as if it is working 'better' than it was 20K ago.. was going to take a crack at adjusting it to shift correctly when summer/dry weather arrived.

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46 WDX Power Wagon

84 300TDT daily driver

No one is perfect; the apply pin will make a big difference in the way that car drives. MB manual can be expensive to rebuilt, hard parts are costly. Manual can be tricky and frustrating if you don’t know the disassemble, reassemble sequence, you will need specialty tools, bearing pullers , installers, snap ring pliers, and most important, the experience to identify a bad or useable part. Do a search on the diesel forum for the vacuum problem



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I just played with them for a while, when I was 17 years old, every make and model , automatics , manuals, transfer cases and differentials, five days a week for the past 36 years.