charging a/c low & high pressure hose valves

[abe g]

On my 450sl (1977) I have running r-12 system. How do I locate schrader valv One hos with valve runs from evaporator (this is above lower hose) running to compressor. any diagram possible? Thanks all, Abe Ges (2) for correct low pressure chrging?

You need a manifold set and monitor both low and high when charging. You have found the low side. The high side will be between the compressor and filter drier or on the filter drier.

You can get a great book from www.ackits.com that will give you the basic information you really should know when doing a/c work. Without it or its equivalent you are risking your safety and the safety of your car.

Good luck,

[ladomani]

Hi Larry

How can one know when the drier should be changed or i s due for change?

Are there any symptoms ? Infact is there any seervice routine for A/c system in a car as you would do routine maintenance on ur car?

thanks

ladomani