The AC in our 97 80 Series was underperforming in the recent Texas heat wave. I couldn't tell what brand or version of fan clutch was in the vehicle, but it looked very old, so I put in a brand new Aisin blue fan clutch. A week later and still not happy with the AC condenser performance, I disassembled the blue fan clutch to adjust the valve opening temp and put in some 20k cst silicone oil. When the two halves of the clutch came apart, the square section O-ring was not a continuous ring. Not sure if Aisin are using spliced rings or if it just stuck to surfaces on either side and it just sheared when being disassembled. I searched the forum and the one previously referenced O-ring source I found 'Wits End' seems to no longer have this O-ring on their site. I am debating whether to clean up the ends of the O-ring and use some cyanoacrylate glue to stick it back together. Maybe placing some RTV across the glued section when assembling for insurance. Anyone know of another source for these O-rings. Another option I am contemplating is to try and determine what make and model the old fan clutch is and try to rebuild it with some appropriate viscosity silicone fluid. The only distinguishing features on the old fan clutch are the four torx screws holding the two halves together. The hub color is just a metallic color, no paint on it. Below is a picture of the split O-ring from the new Blue Aisin clutch and some pictures of the old 'mystery' brand fan clutch. Your thoughts and suggestions are welcomed.