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What are these parts???

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This is a 2012 Boss 302. These parts were found lying on top of the "shelf" in front of the front away bar. I checks the pulleys, the belts are taut. The car has been driving great except for a "clunk" sometimes when I go over bumps, which is why I jacked the car up this morning. Any and all replied are appreciated. Thank you.
Also, the worn semi circle is not rusty on the inside which leads me to believe these are not old parts a prior owner left there by mistake. I have owned this car for one year.
Hmmm...I took the parts to the local car part store. The guy said it looks like the AC clutch. Just so happens the AC stopped working on my car a month or two ago.
Hi, Grant. Appreciate your reply. I am headed back out to the garage to take another look. Just such a weird spot for those parts to end up if they are not off my car. Thank you!
Appreciate the welcome! Yes, confirmed the AC clutch grenaded itself. I am told it is ok to keep driving the car. Now looking at YouTube videos telling me how to replace the AC compressor. Thanks!

Grant 302

basic and well known psychic
Lookup the procedure to install the belt...I know it changed. One was the 'stretchy' belt...not sure on the other. Might need a special tool to do it.
Had a similar thing happen to my car but the front of the clutch stayed on (barely). Massive cloud of refrigerant exploded out the front of the compressor.

The Ford Repair Manual has a method of using a big zip tie to hold the "stretchy belt" on the crank pulley as you turn it clockwise to seat it.
That made it much easier to get the new belt on. Also there is a kit that adds a tensioner if your engine block already has the mounting holes.
Clean them up with a tap and bolt it more stretchy belt.

I replaced the whole compressor (came already filled with PAG oil) and the receiver/dryer since all the refrigerant had chosen to evacuate itself.
A creative use of extensions is required to get the compressor out.

Picked up a kit with gauges and a vacuum pump to prep and fill the system with refrigerant.
If you're in CA you will need an additional fitting to attach the refill bottles.
Exp. Type
Exp. Level
5-10 Years
Philly Metro Area
I've had a situation with the zip tie method where the belt installed one rib over to far towards the block. I didn't notice it the first time and shredded a belt.

When I went to replace it, it happened again but I noticed it. I used flat webbing about an 1" wide and fed it between the pulley and the belt so that the ribs were floating on it. I was then able to shift the belt over a smidge while turning the pulley and removing the webbing.
Bay Area
I had my compressor clutch grenade on the hottest day of the year. Had to replace the entire unit. Fortunately it was near the end of my extended warranty and that one repair was more than my warranty.

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