R107 SL Air Con

[dandpl]

Hi

I had my 1988 300SL for several years ....the air con has never worked !!!!!

Now I have more time to look at it can any one help me with a basic fault finding chart or similar source of information.

Many thanks from Sunny s.w. France

dandpl

 

[rbarrett]

Start with hooking up gauges to see if there is any freon in the system. If there is, then start testing switches... could be as simple as that. If no charge, then place a vacuum on the system. Pull it down to less than 28 inches and let it set over night. If the vacuum holds over night, then decide if you want to go on with it..the system is tight. Next, is it R12 or R134A? It should be converted to 134A as this is the going, available freon. If you can't do it yourself, take it to a garage and bite the bullet... commit... because it could get expensive... at least you know that the system is tight.. There are several things that could still be wrong...1. Compressor; 2. condenser; 3. expansion valve; 4. Evaporator. The system should probably be cleaned (flushed).... either way, the oil in the system has to be changed out for the 134A... and new oil and freon added. When the oil and freon is in the system, then you can test the rest of the components. There are some items that can be tested prior to the charging of the system like, switches and the clutch on the compressor... mostly, though, you have to decide "I want A/C" and then go for it.