timnjulie Report post Posted April 16, 2023 I recently broke down for the second time due to faulty A/C compressor that locked up, which caused the serpentine belt to fail. The first time was September of 2022 which I wrote off as it being a 2005 Cummins engine in a diesel pusher that it was just worn out, I took it to a Cummins dealer and they replaced the compressor and belt. On my way home from a trip this week the same thing happened again. Seems to be too much of a coincidence? The 24 hours service technician that looked at it while broken down in a parking lot said it appears to just be a faulty part. I’m having it towed tomorrow to their shop for replacement. Any ideas what else may cause two A/C compressors to fail in such a short period? Tim Share this post Link to post Share on other sites
campcop Report post Posted April 16, 2023 As mentioned by the tech, it could be a faulty ac unit, especially if it’s a rebuilt. Do you know what failed? If the belt is too tight that could damage the bearing on the pump especially if the idler pulley is not spring loaded or bad. Also too much or too little Freon could damage the pump. Share this post Link to post Share on other sites
timnjulie Report post Posted April 16, 2023 I was told both times that the compressor locked up and caused the belt to fail. It will be towed tomorrow to the repair shop but initial inspection indicates A/C compressor locked up. Thanks for your help. Share this post Link to post Share on other sites
rayin Report post Posted April 17, 2023 I would suspect the first compressor failed sending metal fragments throughout the closed system. When the second compressor was installed, if they did not also flush the system and replace the dryer unit, it could have allowed said metal fragments to destroy the new compressor. Share this post Link to post Share on other sites
timnjulie Report post Posted April 17, 2023 I spoke with the technician who is putting together new parts he said similar things about fragments. Thank you for your help. Tim Share this post Link to post Share on other sites
frank.bergamo Report post Posted April 17, 2023 Was there PAG oil put back in the system? Look at your receipts. It should be on them if it was done right the first time. No oil or not enough oil will cause the compressor to lock up also. Hope this helps. Share this post Link to post Share on other sites
moonwink Report post Posted April 18, 2023 The compressors have to have the proper amount of the correct type of oil for the refrigerant used. They cannot compress a liquid. All the refrigerant should boil off into a gas in the evaporator. If it doesn't all boil off and some liquid get back to the compressor, it will destroy the compressor or at least wash the oil off the moving parts. Either case will ruin the compressor but trying to compressor a liquid is the fastest way to do it. The metering device may be overfeeding the evaporator. Share this post Link to post Share on other sites