1989 GMC s15 -- Something wrong with AC system
 

I tried to recharge the AC system by using adapter and added R-134a refrigerant...it took about one and half cans of refrigerant and it started blowing cold but than suddenly engine cut off

now whenever I connect that electrical connector to compressor engine cuts off ....so I was told to change compressor...correct me if I have wrong info..

if not any instruction guide to change AC in my 1989 GMC S15


What type of oil and how much oil I should add along with refrigerant?

also how much refrigerant should be added? I mean what is capacity?

Also, any diagram showing low port in this model?

I could be wrong as I don't know when they made the switch, but is it possilble your vehicle is supposed to take R-12 refrigerant?

owners manual or the underhood refrigerant label should show the refrigerant quantity. It probably came with r-12 from factory; check the fittings to see if its been retrofitted. r-12 systems use threaded Schrader valves while r134a use quick connect couplers. r-12 use mineral oil for lubrication while 134 uses pag oil...they are not to be used with the wrong refrigerant. I would add 1oz of oil....usually the oil is injected on the low side after a vacuum is put on the system.


pull the belt off and see if the compressor can be turned by hand. turn the compressor not just the pulley. If the compressor is seized and needs replacement you should do compressor oil balancing. if the compressor grenaded, you should put a screen on the new compressor inlet port to prevent any crud from the old compressor going into the new compressor. Some people check the orfice screen and replace the receiver drier.

Gotta love the mid-july A/C question boom lol

Not to say these off the shelf AC regen kits are bad.... but I would pay the $200 and have my AC system pressure tested for leaks then properly purged then recharged for a reliable AC season.