Hello everybody, new member here with a problem I hope someone can help me with. I recently replaced the A/C compressor on my 2000 300m, (the old one locked up and shredded the belt).

The new one worked great for 10 days, then the belt started squealing and shredded that one as well, so I figured my new reman compressor was bad. However that evening while checking it out, it turned freely by hand.

I have now determined that when the engine is hot, a/c switch off (or engine not even running), and still no belt installed on the compressor, I am not able to turn the compressor by hand. After everything cools down it turns freely again.

Before I throw more money at it here are my questions,

Should I be able to turn the compressor by hand when the engine is hot? (I assume I should)

If the compressor was low on oil would it cause these symptoms?

In case it is normal not to be able to turn it by hand while hot, is it possible that a defective or improperly tensioned belt would cause it shred as it did?


Of course any other opinions or suggestions would be greatly appreciated.

Thanks for your time.

 

The compressor yes should turn freely by hand hot or cold.
When u removed the first one is or was there oil still in the old compressor?
Second did the new one come with oil already in it?

 

Thanks for the response. The compressor was supposed to be prefilled with oil, my mistake for not verifying. I assume that caused the failure.

New problem, after replacing the compressor again, now there is no power at the compressor. It does work by running a jumper from the battery. Relay and fuse is ok, what else do I check? Power wasn't an issue before the compressor failure.

Thanks again for any help you may provide.

 

there is a power fuse and a control fuse make sure all fuses are good

 

I can only find one fuse and one relay that appear to have anything to do with the a/c. What other fuse are you referring to?

Thanks

 

fuse 21 10 amp driver side kick panel

 

There is a fuse #17 located in the drivers side door jamb fuse panel labeled as Heater A/C control. Then there is a relay under the hood labeled A/C Clutch relay. Both of these have been checked.

Thanks

 

fuse 21

 

Fuse 21 (rad fan relay) is also good.