Where's my expansion valve? / '84 190e AC Issues
 

I was topping off my AC with some r-12 and everything was going fine. I had about 25psi on the low side a bit over 200psi on the high side. Then the clutch on the compressor started clicking and when the clutch was engaged the compressor was having a hard time turning. Then WHAM! the relief valve on the receiver drier poped and spit all my freon and color dye (to spot leaks) onto the low pressure valve, and the car stalled. Now when the ac is turned on, (with the low pressure switch bridged) the car stalls.

So, I will replace the compressor and the receiver/drier for a fresh beginning. I should change the expansion vavle too , but I'm not sure where it is on the w201. I know its near the heater core, but is it inside the car? Hard to get? How many hours?

Thanks folks.

One important item with A/C systems is the total charge. OVERCHARGING is very harmful. The 190E uses a max of 2.2 lbs of R12 & only about 1.8 lbs. of R134a.
The expansion valve is underhood near to the brake booster. Just remove the plastic air grill & follow the 2 A/C lines to it. Takes about 1 hr with the system discharged.
One thing about the old GM compressors, the belt has to be tight!

What are HIGH & LOW PSI Ranges?
 

Thanks MB DOC.

Yeah, the early 190E uses that GM R-4 compressor. I do think its shot as the compressor clutch hooks up it stalls the motor. A bad sign.

As for the "blow out" on the receiver / drier , is that shot too? Is it in fact a resettable relief port? Or did it just fail.