Great write up and pictures...Took me about 4 hours thanks to the excellent instructions. One small point that may help others is aligning the plastic collar on the flap that the vacuum arm goes into before trying to put the end of the arm through it.
If you look at the arm of the pod that is mounted just on the outside of the airbox (defrost I think) for reference you will see what I mean. I had it hooked in the flap but had to remove it to turn the collar so I could get it completely seated.

I had a couple general questions about these pods. Is there any acceptable amount of leak down on them? I have one that slowly leaks down vacuum after about 5 minutes. Its the one by the gas pedal.
Also, in following the instructions in the FSM on testing the fresh air pods (behind the glovebox) I discovered that they don't hold vacuum unless the other line that goes to them is plugged. For example if I pull the bottom green blue line off the lowest of the switchover valves and vacuum it out it doesn't hold unless I plug the red one above it that goes to the same circuit. Is this normal?

Any help would be much appreciated and thanks again for the great directions.

Thanks for mentioning this. You know what? I did have trouble with that inserts orientation. I just thought nobody was as dumb as me so I didn't bother mentioning it. . Yep, I had to rotate it around with a screwdriver before the hook would seat.

As for your behind the glove box pods I would say what you are seeing is not normal. I have new and old ones (old are bad) on the bench and the good ones hold vacuum on the red and green/blue ports. I'm testing directly on the pod. I got away with one bad pod for a long time because there are two pods. The flap just worked slowly. Also there is a big spring on the red side that works in the green side's favor.

I think the vacuum pump can keep up with a leak rate that drains the mityvac in 5min. Remember there isn't much volume in the mityvac. The car has the pump and the reservoir tank. But it does sound like you have a pinhole in there. Based on my experience with these pods little leaks lead to big leaks as time goes by. If it works you can keep using it till it doesn't. You won't have far to look when it comes time.

__________________
79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles
97 C280 147k miles

Hey, I just went down to the garage and played with a good double action pod from behind the glove box. Yes, it holds vacuum on the green and red side. If I had to guess you have at least two punctured diaphragms on one or more of the pods. You are pulling air through the green circuit and it is leaking in through the red circuit because both diaphragms in one or both pods have holes. I guess the red circuit would normally be plugged if you left it on the switchover valve and the car was shut down. But that wouldn't do any good because the pod actuator won't move if you pull on the green circuit and it just connects right through a series of punctures to the red side and clear back to the red switchover valve.

Sounds like it's time to pull both pods and check them independently. Good luck.

Btw - on the 1982, one of the recirculated air pods on the back of the glove box 0008003775 is no longer available from MBZ/Behr. These have the three teets and starlock nuts on the back. If you're lucky you'll have the later ones with the bayonet mount. I had to "make" one out of a 0008003675 by removing the little metal arm from my old one and riveting it to the new one. I think I had to also change the orientation of the green housing relative to the pink housing.

Things like this are making me realize I need to think of a future without this car.

__________________
79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles
97 C280 147k miles