I have a '81 300SD and the air conditioning does not work. Before I go to an expensive air conditioning repair shop, I would like to know if there are some specific parts I could buy on Ebay or something, replace them myself and then get the system recharged. Any thoughts would be greatly appreciated.
Thanks.

try doing a search and following some procedures spelled out on one of the online FSM's. You need to know specific symptoms before you start buying parts willy nilly. It could be as simple as a fuse or something very expensive. Until you do that you have no way of knowing.

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Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
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Section 609 MVAC Certified
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