AC belt melted

[Twiss]

14SierraSLE5.3L

Short hand summary.  

-Cold air quit, popped hood, ac belt shredded and melted.  Melted to only a third of the compressor pulley, but 100% of the balancer (suspected compressor locked up).

-Cleaned pulleys, replaced belt, compressor pulley spins freely (doesn’t have typical clutch that remains stationary when not engaged).  No cold air

-Pressure looked low (hard to say when you don’t know if the compressor is engaged), tried adding some 134, it took some from the can, then killed the motor.  Suspect the compressor engaged and the drag from the belt stalled the motor.

 

Before I replace compressor and the works, any suggestions on testing the system/compressor.  The non visible clutch is really throwing me for a loop.

[Snowcamo]

Hey i am going through the same deal. The compressor is toast as in locked up. I am not sure which repair route ill go as I have lifter issues as of yesterday... 

 

Id suggest compressor, lines, metering device and filter. Its just the compressor likely tho.

 

This is an important question. 

Before it failed did you notice a snatching sound when the ac turned on first start? 

[Twiss]

16 hours ago, Snowcamo said:

Hey i am going through the same deal. The compressor is toast as in locked up. I am not sure which repair route ill go as I have lifter issues as of yesterday... 

 

Id suggest compressor, lines, metering device and filter. Its just the compressor likely tho.

 

This is an important question. 

Before it failed did you notice a snatching sound when the ac turned on first start? 

I’ll do the works (compressor/condenser/orifice tube/dryer/etc), but first I want to be sure it’s not something petty like a hi or low side switch.

The only thing I noticed was the day before after hauling my boat for 4 hours there was some “smoke” from under the hood.  Didn’t find leaks and it wasn’t obvious to be coolant or oil (however I didn’t think to look at the belt).

 

I’m still trying to figure out how you know when the compressor is engaged, it’s not like any previous ac clutch I’ve seen.  The entirety of the pulley is always rotating with the belt, whether the AC is off or on.

[Snowcamo]

1 hour ago, Twiss said:

I’ll do the works (compressor/condenser/orifice tube/dryer/etc), but first I want to be sure it’s not something petty like a hi or low side switch.

The only thing I noticed was the day before after hauling my boat for 4 hours there was some “smoke” from under the hood.  Didn’t find leaks and it wasn’t obvious to be coolant or oil (however I didn’t think to look at the belt).

 

I’m still trying to figure out how you know when the compressor is engaged, it’s not like any previous ac clutch I’ve seen.  The entirety of the pulley is always rotating with the belt, whether the AC is off or on.

The hp or lp saftey switches only turn off the comp. Not lock it up. 

 

I'll suggest seasons4 for replacement parts. They have the vehicle ac stuff perfected.

[Twiss]

37 minutes ago, Snowcamo said:

The hp or lp saftey switches only turn off the comp. Not lock it up. 

 

I'll suggest seasons4 for replacement parts. They have the vehicle ac stuff perfected.

I appreciate the suggestion.  Do you know anything about the clutch on these compressors?  Typically the center of the pulley is clutch location and is stationary until it engages.  Mine is not engaged, but the entire visible assembly spins freely??

[Twiss]

37 minutes ago, Snowcamo said:

The hp or lp saftey switches only turn off the comp. Not lock it up. 

 

I'll suggest seasons4 for replacement parts. They have the vehicle ac stuff perfected.

I appreciate the suggestion.  Do you know anything about the clutch on these compressors?  Typically the center of the pulley is clutch location and is stationary until it engages.  Mine is not engaged, but the entire visible assembly spins freely??

[Snowcamo]

On 8/31/2021 at 2:22 PM, Twiss said:

I appreciate the suggestion.  Do you know anything about the clutch on these compressors?  Typically the center of the pulley is clutch location and is stationary until it engages.  Mine is not engaged, but the entire visible assembly spins freely??

I do not know what's up with the clutch. I'll pop the hood tomorrow and see if mine spins as well. I didn't really care atm as I was pissed lol.

[CrawlSlow]

Just confirmed on my 15 LT 1500, the AC clutch engage only when AC is on. It spin freely when not engaged. There's nothing special about the AC clutch. 

 

Sounds like your AC clutch locked up. 

[Twiss]

19 minutes ago, CrawlSlow said:

Just confirmed on my 15 LT 1500, the AC clutch engage only when AC is on. It spin freely when not engaged. There's nothing special about the AC clutch. 

 

Sounds like your AC clutch locked up. 

Can you post a 2 sec video?  Doesn’t sound like the same compressor.

[CrawlSlow]

Will do when I'm off work. I have a 5.3 1500. The compressor clutch look the same like any others I worked on before. Same concept, engage when it's on, disengage when off. 

 

Take a picture of your compressor and clutch.

[Twiss]

1 hour ago, CrawlSlow said:

Will do when I'm off work. I have a 5.3 1500. The compressor clutch look the same like any others I worked on before. Same concept, engage when it's on, disengage when off. 

 

Take a picture of your compressor and clutch.

This is NOT engaged…I don’t see a clutch remaining stationary?

[Twiss]

[Twiss]

What looks like the clutch spins with the pulley AC on or off / HVAC powered off / set to heat (no defrost). I think I’ve confused myself more now.

[CrawlSlow]

The outer part is the clutch. 

[Twiss]

21 minutes ago, CrawlSlow said:

The outer part is the clutch. 

In that case it runs all the time, no matter what is turned off or on.  It doesn’t produce cold air, and evidently locked at some point to melt the belt.