W124 A/C Compressor Noise?
 

Well Larry, you started that thread asking where all the a/c posts were..here's mine..



In my 91, my a/c was converted from R12 to R134a back in 2010 by the previous owner. The fittings where changed and a sticker was installed. Not sure what else was done but thats all that I can visibly see.

I had to add a can of R134a a few weeks back as it has evidently leaked out?

Since the recharge it has been doing well though, nice and cold, no complaints about that.

I do notice some odd sounds from the a/c compressor when its engaged. I've attached a video here for you to listen. When I put the climate control into EC mode the noise goes away so I figure its either a) from the a/c compressor or b) caused by the additional load of the a/c compressor...

Video:

http://img.photobucket.com/albums/v6...ps5438b879.jpg

My questions:

1) Is this indicative of compressor failure?

2) Low oil?

3) If 1 is true, would it be worth while to buy all the necessary components to make this a true 124, 134a system? If so, what would those components be? new condenser, compressor and o-rings?

I take it, the noise is only present when the AC is on...
it sounds like power steering to me... the compressor could be loading the belt and letting the PS slip...

Yep only when A/C is engaged.

Hrmm.

I'm not all that familiar with the belt tensioning system on this engine. Can it be tightened? or should I just leave well enough alone? Or bad belt?

bump?

Are you referring to the whirring?

yes, you can hear it as the engine revvs up

I dont think a compressor can make that noise. What is the age of your belt? I know with my m103, if the serp belt gets old or loose it will whine like that.

If you can deflect the belt more than 1 inch it is probably too loose. It does sound a little bit like a whiney power steering pump. Did you check that too?

It might be the belt..I'm not sure. Records show replacement at 198,000...What's the belt change interval on serp belts?



It only occurs when the a/c is engaged, otherwise its silent.

You replace the serp belt when its worn. If you aren't sure when it was done last... just replace it. A quality belt is only $30 or so (same as a GM 3800 V6, so they're easy to find). Also give your belt tensioner a long hard look. It should have no axial play, and the damper should still be in good shape.

-J

I do 5 years/50k. Visual inspection trumps all. If it has cracks, change it.

Modern belts won't get cracks when they wear out... the Vs just go flat.

I dont know what your definition of "modern" is, but I have seen plenty of serpentine belts with cracks in them.