Bran, don't try turning on the compressor again until you verify this.
I'm getting a bad vibe from your two threads. You say that the compressor throws the belt when you turn it on. Does it do it as soon as you hit the switch, or after a short time. You also asked how to set the pressure switch.
Taking those two together makes me wonder about the high side pressure.
Before you turn the compressor back on, put a high side gauge on the system. With the system off for at least a couple of minutes, the high side and low side should be the same.
If the high side is higher, STOP.
Do Not turn that system back on until you have found the blockage.
If the pressures are equal, turn it on and watch the high side with your hand on the switch. If it starts climbing fast, going past 300 and heading higher, kill it. You have a blockage, probably in the drier.
A blockage there would cause the pressure switch to trip out because it was being starved for freibergs.
Sorry, I had to......
But a high side blockage would cause way too much load on the compressor, or cause it to lock up entirely, both of which could cause it to throw the belt. And could also cause a line to explode.
I see too many people charging a system with only the low side gauges. Very bad idea. I especially like the do it yourself kits they sell now in parts houses that you just hook to the low side and put in gas until the built in gauge says its full.
Great way to destroy a compressor or blind someone when a hose ruptures.
Otherwise, the only way rust would cause the belt to jump off is if the grooves in the compressor pulley were full of rust or dirt. A hand wire brush brushing with the grooves should take care of that.
