LannyL81

On the one I took off my car there is what looks like a relief valve screwed into the rear of the compressor next to where the lines connect. On the replacement compressor, there is not. The hole is not drilled out from when the part was cast. Is this the high pressure relief valve or something? I am not wanting to drill and tap this hole as it would result in metal shavings inside the compressor. Can I still use this or does it need to go back?

Thanks,
LannyL81

mrvette

You are fine,...go for it....no sweat....do not drill/tap anything....

wnmech

I agree with you thinking it is a high pressure relief valve. If it was me I would go back to the vender to see if he has one with the proper holes for the valve. Is there a spot on the new compressor that has a snap ring installed? Some different types of R-4's have a relief valve switch that is held in with a snap ring and when you get the compressor from the vender it will have a plug in that hole which means you may have to buy a different switch to make it work properly.

Jud Chapin

I would tend to agree here, but mrvette may be correct. Here is an a/c forum where you can get more opinions from those in the trade.
http://www.autoacforum.com/categories.cfm?catid=2

LannyL81

Checked out that site and WOW...learned more about the R4 compressor than I ever wanted to.....thanks. Still have not found out what for sure this thing is on the back and if I even need it. The compressor I took off was not original. Any 81 owners out there with an original AC compressor??

Thanks again to all,
LannyL81

comp

Jud Chapin

Lanny, if you sign up for the forum, you can ask your specific question about the pressure relief valve. Most of the guys who respond are in the trade and can tell you what you need to do, if anything. Good luck.
Jud