This is a friend's car. I replaced the condensor, compressor, and receiver/drier and flushed all lines about a year ago due to catastrophic failure. He has left the car with me over the weekend to work on a few other things. In working on the car, I discovered a massive leak of PAG oil coming from the vicinity of the receiver drier. Fortunately when I charged I used U/V dye, so tonight it was very apparent where the leak is coming from. It seems to be the little black pigtail that sticks off the top of the R/D; either that, or possibly a bad high-pressure line. I can't really tell, so I will go in there tomorrow morning and snug up the lines. But does anyone have any experience with the R/D leaking from that pigtail thing? It's not a pressure switch, as it doesn't have any wires going to/from it. It's just a black extension that protrudes from the top of the R/D.

See the picture below - it's the hex-shaped extension coming off the top. Any ideas?

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280

The hose to the R/D is a common leaking point on these cars. Might be a good idea to just replace it while you are there.

Len

You mean replace the hose? Or the receiver drier?

It's been a while since I replaced it - do you recall if there's an O-ring in there? I may just replace the O-ring, vacuum, replace oil, and recharge.

Or are you saying the hose tends to leak and it should be replaced?

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280

Yes, the hose leaks and needs to be replaced. Probably ought to replace the R/D then too.

Len

That is the overpressue relief, and you have either a plugged expansion valve or a bad relief valve. Pressure check will tell you. If the oil is only around the fitting and not coming out of it, it's the o-ring, and they are a funny size, not in the usual assortments.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Thanks. What relief valve are you talking about? You mean the blowout valve on back of the compressor? Or is there a separate relief valve somewhere inline on the W210? Also, at what pressure does the pressure relief on the R/D typically vent?

__________________
08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280