When I redid the AC system on my '76 Century I removed all the cracked insulation off the hoses. The ac works great down the highway but starts to warmup at idle. After reading another post I'm thinking the insulation can't hurt. Does anybody know where you can get some of this? I don't want to remove the hoses again so I'm thinking I could split them and just tywrap them on. That should help efficiency some.
Insulation is not your problem......get a set of gages and take a reading at idle with ac on max and fan set on high......sounds like your system is low and/or has a small leak.
Actually, the#1 cause for reduced AC cooling at idle/low speeds is a weak fan clutch. The fan clutch is also the most often overlooked component of the AC system. The AC system id very dependent on airflow across the condenser to remove heat. The very first sign of a weak fan clutch is reduced AC cooling at idle. This will happen Loooong before you notice a change in engine temperature. The clutch is actually a "wear item" with a typical life span of about 10 years. Mist your condenser with water and see if the vent temps drop briefly. If so, the fan clutch is weak. Ideally you would do this and watch for a sharp drop in the High side system pressure, so if you happen to have a manifold gauge set, do it that way.
