Air conditioning noise and vibration

[Paul G]

I can remember when these cars were new, the A/C coming on would drag down the engine, you could feel the power loss but not really cause a lot of strange noise and vibration.

Now up to today, my 72 will make a lot of unusual noise and vibrations, grunts and groans when I turn the steering wheel, but only when the A/C is running. It has a Sanden compressor with an r134 conversion system kit from Bouchillon. March serpentine pulley set with two serp belts.

When I had the 73 it also had a Sanden compressor, the system was converted to r134 with the rest stock. It too made a lot of strange noise and vibration, grunts and groans, only when the A/C was on. It was using the stock style two V belt pulley system with a Sanden compressor.

My compressor is bolted down tight. I dont know what would cause this noise and vibration, or if others eperience this? Is it the nature of a Sanden compressor to be noisy? The system works great, ice cold. Just noisy with vibration when it is on. Turn it off and back to normal, like it is not even there.

[elacruze]

This is usually because of loose belts.

If you have a serpentine setup, use a torque wrench to measure the tensioner pulley. Take a measurement with the torque wrench 90* to the pivot/pulley axis. If I recall correctly, it should take no less than 35 lbs-ft to lift the pulley from the belt. You'd be amazed how many tensioners don't meet the spec even new out of the box.