- Jun 26, 2019
I've been installing r4 compressors on my 1980 Pontiac Grand Lemans and GMC Caballero. One was new and the other was a reman. What a nightmare! About 20 years ago the design of the hose manifold connection changed. The old square-cut o rings were replaced with Mickey Mouse "washers." I finally got the Pontiac working by using a big, plain seal and a green one. That combination didn't work on the Caballero. I had to use a red one and a green one to get the sealing surfaces even before installing the manifold. Three techs at Fourseasons told me different things about the seals. The Caballero system is leaking so I'll spend the day trying to identify the leak. I have no idea why the compressor design was changed.