air conditioner in 740-which type?

I brought my '87 740 GLE in to get the a/c recharged. The mechanic
said the a/c was labeled with one type (there's a plastic tag that
says: R134a) but the nozzle or connector was a different type, so he
didn't want to recharge it. I don't know what to do. I would
appreciate any suggestions.

-Jim

 

It originally had R12, but it sounds as if it's been retrofitted. If in
doubt it wouldn't hurt to spend the $100 or so to install a new retrofit
kit, if the charge has leaked out it probably needs new O rings and a new
reciever/dryer too, that's the bulk of the cost of the kit.

 

by Jim dropped his wrench, scratched his head and
mumbled,

If the shop can't test the refrigerant to determine what's in it, then
find a shop that can. If the shop that did the "conversion" didn't change
the service port fittings to the proper type, then find a shop that can
do both these things correctly and have the system repaired to operation
in a proper manner.

Bob

 

The only proper way to be sure is to find a shop that has a refrigerant
tester. They can take a sample out of the system, and their machine
will test it and tell them what it is. Chances are you have 134a, and
what should have been a permanent conversion fitting was only
temporarily attached over the R12 fitting to do the initial fill and
then removed.

 

If you have a full charge its ez to tell if its 134a or 12. 134a will warm
up when you stop at a redlight, 12 wont.