AC compressor bearing going out?

[CamasM3e93]

Last couple of days I've noticed a quiet high pitched sound from the engine compartment that I associate with roller or pulley bearings. The water pump and every pulley in my car were replaced this year and the Harrop rollers are not the culprit. This morning it came back as I was pulling into work (or that's when I noticed it) and isolated the sound to the passenger side of the engine bay, in front of the engine. Turned the AC off and the sound disappeared.

I know others have reported trouble with AC compressor failures. Wonder if folks have had similar issue leading up to the failure.

[NiBe]

Do you have enough freon in your AC?

[CamasM3e93]

Originally Posted by NiBe

Do you have enough freon in your AC?

I did a top off on my own earlier in the season and based on visual pressure measurement I'm right in range. BMW quotes a very specific and narrow mass of refrigerant for the system so it's possible I'm running on the low (or high) side of that but getting excellent cooling.

[NiBe]

Originally Posted by CamasM3e93

I did a top off on my own earlier in the season and based on visual pressure measurement I'm right in range. BMW quotes a very specific and narrow mass of refrigerant for the system so it's possible I'm running on the low (or high) side of that but getting excellent cooling.

If you are getting excellent cooling then the freon is fine. I read somewhere that some sound can happen when you are super low on freon.

Good luck with finding the real culprit, The AC bearing/clutch seems as a candidate.

[Scharbag]

Originally Posted by NiBe

If you are getting excellent cooling then the freon is fine. I read somewhere that some sound can happen when you are super low on freon.

Good luck with finding the real culprit, The AC bearing/clutch seems as a candidate.

Technically R134A is not Freon…

[tbuck]

This is not coolant related, the coolant does not lubricate the AC compressor. Some types do use oil in with the coolant, but this is not one of those. Also it is very rare for the AC compressor itself to have a bearing go out. My guess would be it is the clutch/pulley assembly on the compressor. I have seen that happen a number of times over the years.

At one time I purchased a cheap compressor and swapped out the pulley on a Honda we had a while back. Main reason was to not break the seal on the R134 that had been working perfectly for years. Put the new pulley on and all was quiet. May not be worth it on this platform....

[tdott]

I found this AC compressor clutch bearing and pulley replacement on ebay: https://ebay.us/BOcRaB

No idea if it can be done in the car though, might still need to be removed from the car.

110D7E7617
A/C Compressor Clutch Kit
DENSO 7SEU17C 6PK (PV6) Ø110/Ø110 BMW

[CamasM3e93]

Originally Posted by tdott

I found this AC compressor clutch bearing and pulley replacement on ebay: https://ebay.us/BOcRaB

No idea if it can be done in the car though, might still need to be removed from the car.

110D7E7617
A/C Compressor Clutch Kit
DENSO 7SEU17C 6PK (PV6) Ø110/Ø110 BMW

I can't recall specifically, but you definitely can't remove the clutch assembly without a special tool. I bought a generic adjustable one and it ended up stripping the tool and clutch wheel out. It was ok because I was set up to do the entire unit and was really just messing around to see if it was feasible to do clutch only.

Can't swear by it but I do think it's possible to leave the compressor in the car but it'd be tight. I pulled my fan and radiator to do the entire unit swap.

If you're setting the job up and looking to do the clutch only, would look to get the removal tools specific to the compressor version.