How to get rid of the sound? - United Bimmer Community

**zeaq328i** · 05-02-2006, 01:04 AM

Well whenever I switch on the AC, there will be a fan sound which is normal and one sound which really annoys me. There will be a” bearing like sound”. The compressor and the belting are changed recently. What else can it be?

I hope you know what I’m saying.

**zeaq328i** · 05-02-2006, 01:22 AM

http://files.unitedbimmer.com/ub.c/z...ound%20air.MPG

Here's the short video.

Notice the bearing sound not the fan sound.

**celsdogg** · 05-02-2006, 01:45 AM

i think im missing it. . . but it is almost three in the morning. . .

**c1apton** · 05-02-2006, 03:36 AM

"Z", from your video it sounds like the AC cycling in & out. When they recharged the AC system did they evacuate the system? Also when they recharged did they add oil to the system?

**zeaq328i** · 05-02-2006, 06:32 AM

^^Well i'm not sure. I assume they do it.

By the way, what do you mean "AC cycling in and out?"

Did you hear the "bearing like sound"?

**c1apton** · 05-02-2006, 07:16 AM

Quote:

Originally Posted by zeaq328i

^^Well i'm not sure. I assume they do it.

By the way, what do you mean "AC cycling in and out?"

Did you hear the "bearing like sound"?

Yea, I heard it. I had to enhance your video to hear it better but yea there's noise there. AC cycling = when temp is set to a certain temp the compressor "kicks" in & out to remain at that temp. I'ld check with the guys who did the install & ask if they used freon w/oil. If not have them add it. (the oil lubricates the seals & compressor bearings internally & helps the system seals at connections. BMW uses different alloys aluminum, copper, etc & these different metals expand/contract at different rates at different temps, so keeping seals lubricated is critical)

**Dudesky** · 05-02-2006, 07:22 AM

Isn't the cycling normal?

Storamin · 05-02-2006, 09:10 AM

Did they flush the system prior to adding more in?

**BMWLotAttendant** · 05-02-2006, 10:59 AM

Sounds like a lawn mower.

Hope you get it solved.

What happens if Z does nothing?

**c1apton** · 05-02-2006, 11:44 AM

Quote:

Originally Posted by Dudesky

Isn't the cycling normal?

Yea, cycling is normal but bearing noise isn't. (he wanted explanation of cycling)
He'll lose a compressor prematurely if there's no oil in the system.

**zeaq328i** · 05-02-2006, 11:46 AM

Thank for explaning it Claptop.

Well could it be the sound of the Tension pulley? Now my brain starts to remember, when changing the compressor last year, he did said the tension pulley have to be change but not critical.

But i bring it for the annual oil service and they change the belting.

To my suprise the there's no sound when the AC is on .Only the fan sound which is normal.

But now the anoying sound slowly started to come back.Now it's not loud.

BMWlot,

i think if i didn't do anything, the ac stop working in the future?

:

**c1apton** · 05-02-2006, 11:52 AM

Quote:

Originally Posted by zeaq328i

Thank for explaning it Claptop.

No problem "Zeb" j/k

**zeaq328i** · 05-02-2006, 11:54 AM

^^Don't be mad...

Well could it be the tension pulley?

**c1apton** · 05-02-2006, 11:58 AM

Quote:

Originally Posted by zeaq328i

^^Don't be mad...

Well could it be the tension pulley?

I'm not mad at all, it was pretty funny..

Yea it could be the tensioner - they're notorious for bearing noises too. That you'll have to actually look at for signs of wear (heat marks, small metal shavings possibly, black dust/grime - like what your wheels look like from brake dust - just a few that come to mind) I'm not sure of your AC belt configuration but if it's seperate from water pump & alt, you could always pull the AC belt and see if noise goes away.

**zeaq328i** · 05-02-2006, 12:02 PM

Will "WD-40" do the trick?If i spray on the belts.