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:



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?

__________________
Cruise Control not working? Send me PM or email (jamesdean59@gmail.com). I might be able to help out.
Check here for compatibility, diagnostics, and availability!

(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


82 300SD 145k
89 420SEL 210k
89 560SEL 118k
90 300SE 262k RIP 5/25/2010
90 560SEL 154k
91 300D 2.5 Turbo. 241k
93 190E 3.0 235k
93 300E 195k

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...

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

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?

__________________
Cruise Control not working? Send me PM or email (jamesdean59@gmail.com). I might be able to help out.
Check here for compatibility, diagnostics, and availability!

(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


82 300SD 145k
89 420SEL 210k
89 560SEL 118k
90 300SE 262k RIP 5/25/2010
90 560SEL 154k
91 300D 2.5 Turbo. 241k
93 190E 3.0 235k
93 300E 195k

bump?

__________________
Cruise Control not working? Send me PM or email (jamesdean59@gmail.com). I might be able to help out.
Check here for compatibility, diagnostics, and availability!

(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


82 300SD 145k
89 420SEL 210k
89 560SEL 118k
90 300SE 262k RIP 5/25/2010
90 560SEL 154k
91 300D 2.5 Turbo. 241k
93 190E 3.0 235k
93 300E 195k

Are you referring to the whirring?

__________________
Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2

yes, you can hear it as the engine revvs up

__________________
Cruise Control not working? Send me PM or email (jamesdean59@gmail.com). I might be able to help out.
Check here for compatibility, diagnostics, and availability!

(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


82 300SD 145k
89 420SEL 210k
89 560SEL 118k
90 300SE 262k RIP 5/25/2010
90 560SEL 154k
91 300D 2.5 Turbo. 241k
93 190E 3.0 235k
93 300E 195k

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?

__________________
Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2

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.

__________________
Cruise Control not working? Send me PM or email (jamesdean59@gmail.com). I might be able to help out.
Check here for compatibility, diagnostics, and availability!

(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


82 300SD 145k
89 420SEL 210k
89 560SEL 118k
90 300SE 262k RIP 5/25/2010
90 560SEL 154k
91 300D 2.5 Turbo. 241k
93 190E 3.0 235k
93 300E 195k

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

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

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

__________________
Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2

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.

__________________
Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2