Dgreen wrote:Well, I changed the bearing and still have a noise. Also tried a different hub plate. Only thing I haven’t tried is a different coil and pulley. I put a stethoscope on the compressor and it sounds good.
Is it possible that the coil is weak and letting the clutch to slip and causing it to make noise?
Are ALL of the mounting brackets tight and in place? Is the system overcharged?
Dgreen wrote:Is it possible that the coil is weak and letting the clutch to slip and causing it to make noise?
If clutch is slipping, that should be evident visually.
I just last month fixed an intermittent slipping AC clutch on my 1998 Frontier. I removed a shim under the drive plate, and now it works fine. When the air was coming in warmer, I immediately pulled over, opened the hood, and could see that the clutch stopped engaging when it had power, because I had installed a dash light in parallel to let me know when the AC clutch was getting power.
I have the coil off and will try a different coil tomorrow. If it still makes noise, I’ll recover some refrigerant. I think 40:oz was the factory r12 charge. System currently has 36 oz of r134a in it. Low side was sweating heavily all the way back to the compressor. Over charge might be a possibility.