I hope the dealership didn't charge you money for the non-fix. That would be unjust enrichment, the legal term. You were paying for a fix.

I do tighter than finger tight, but not gorilla; so that's not much help. With an O-ring, the compression forces the O-ring to expand and seal. So I'm saying firm, and when you pull a vacuum or check with bubble solution after refrigerant fill, you should know if you need to tighten a tad more. Use ...

Wyattgc wrote:Would I need less r12 if I did seal off the rear ac?

Absolutely !!! And likely the new R4 compressor would last a ton longer. It's lower lifetime in dual-AC vehicles has been documented due to liquid refrigerant from the rear getting back into the compressor.

Someone here will know if this vehicle is able to be converted successfully to R134a. Original R4 compressors worked OK, had marginal lifetimes when used with rear evaporator, so blocking off the rear should help. There are conversions to use more-modern compressors in this however. My guess biggest...

2.5 years ago when I needed to replace the compressor in our 2005 GMC Yukon Denali I installed a brand new Denso one, OEM supplier, was bout $200. Not worth saving $20 to install a rebuilt. Make sure to get one set up for dual or front-only air, they typically are different. I installed a Four Seaso...

BOON250 wrote:If I rev to about 2500 the high side goes to 200 and the low side stays at 19-20 . Never moves. Vent temps stay the same.

Vent temperatures get lower when driven. Try it out on the road on a hot day.

Your 2500 rpm pressures seem a little on the low side.

R134a is still $4.88 per 12 ounce can at U.S. WalMart stores. No additives. https://www.walmart.com/ip/Super-Tech-Refrigerant-R-134a/617476716?wmlspartner=wlpa&selectedSellerId=0&adid=22222222227084651175&wmlspartner=wmtlabs&wl0=&wl1=g&wl2=c&wl3=199458688998&wl4=pla-3...

srkreutemazda wrote:2000 Mazda b2500 with 2.5L engine. I'm in Fl.

Also know that this vehicle is really a Ford Ranger, and made in USA. Some of the Rangers had factory AC, some had dealer-installed, parts were not necessarily the same.

That's a good idea for him to check.

Also worth checking is to remove the rear case and make sure that the rear evaporator fins are clear and not all clogged up.

15 years ago I bought a rebuilt compressor that came filled with PAG oil (I tested it). My '88 Mazda truck is R-12. I drained the oil from the compressor, added 6 oz. R-12-type mineral oil, rotated the compressor about 15 times by hand, drained that out. Then I repeated that. Then I added the correc...