noob w/ 722.120 Question, B2 servo ??
 

greetings everyone!
I am the lucky new owner of a 1980 300sd w116, problem is that I bought it needing trans work, Here is the issue-
engine starts and runs fine, but when shifted from park, there is no movement or activity at any rpm. sounds like a B2 servo, BUT there is no reverse either. I have dropped the pan and valvebody and the internals look very healthy. can anyone here help me solve this mystery ?

Thanks !

Those transmissions are known for breaking off the ears which drive the front pump. Check to see if you are getting any fluid pressure. Pull one of the coolant lines, run the engine and see if anything pumps out. If nothing does, front pump is not working.

Roger that, from the voice of experience.

The B2 servo issue is more of a 722.3xx weakness. The front pump/TC and the loss of reverse (reverse band adjustment backs out-had that ,too) are classic 722.1xx

thanks guys, this has to be the first time ive gotten a response when using a forum, i like this site already! looks like I will have to source a used trans to swap in, is there anything I can do to prevent this from happening again?

Yeah, don't drive it.

Swapping in a used front pump and torque converter isn't too hard (once you have wrestled it to the ground). If yours seems clean and has low mileage, there is always that option.

I briefly worked for a shop that would sell the customer a complete rebuild when a 722.1xx came in with the reverse band adjustment backed out....Robert