I have charged the leaky a/c in my 1988 244 enough times to know every way to not connect to the low side compressor port.

Also, here's a test to see if low pressure is causing the compressor to not engage.

Connected to the top of the receiver drier (mounted on the right end of the radiator)is a wiring harness. Raise the harness connection just a little, but leave the wires connected. Slip a key or paper clip or coin into the opened space and jump the two connectors. The compressor should kick in with a nice loud "clack". Remove the jump quickly, the system may also be low on the refrigeration oil needed to lubricate the compressor.

I have a full size gauge and hose set up, so the hoses are nice and long. The one for the low port has a 45 degree bend at the end, making the job a little easier.

Two routes, neither is joyful.

(1)
Atep 1. Remove AMM, connect hose, install AMM.

STep 2. Put on safety glasses and do the job.

Step 3. Remove AMM, disconnect hose, connect AMM, start and drive cool.


(2) Step 1. Put car on ramps. Have Go-Jo available. Let correct hose drop down from above so the end is near the low port (the one away from the block).

Get under the car, use your long thin prehensile fingers to remove the port cap and connect the hose. Port cap may need pliers to loosen.

Step 2 - Climb out from under, put on your safety glasses and do the recharge job.

Step 3 - reverse of Step 1.

Better to underfill than to over fill. If you are using an R-12 alternative, like Econocool or Freeze-12, be sure to use the correct amount or a little less. I believe that with those two the bubble glass may be a liar.

Good Luck,

Bob

:>)