Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 09-23-2003, 02:29 AM
Registered User
Join Date: Mar 2000
Posts: 532
Variable Displacement Compressor Failure - What Happened?

A friend's '98 C230, 44K miles, recently lost the A/C compressor... the unit briefly made a clunking noise when engaged... shortly afterwards, the noise stopped, as did all cooling. The clutch continues to engage when activated and the pulley turns smoothly but the compressor is quiet and high side and low side pressures remain identical.

The local dealer says they've begun to see elevated failure rates for these compressors.

What happened here? M-B offers a reman'ed unit but this is not a cheap unit to replace. Thought the variable displacement compressors were more reliable than the previous generation of NDs.
Reply With Quote
Old 09-23-2003, 10:06 AM
MrCjames's Avatar
California Dreaming
Join Date: Jun 2003
Location: SF Bay Area
Posts: 599
One of the problems with R-134 systems is the oil does not blend with the refrigerant. Another issue with the oil being used in the system, it is "Agroscopic" meaning moisture will mix with it thereby effecting the oils ability to reduce friction over time. Another factor could be if your system had a leak prior to this failure, and the oil in the system was not replenished to its proper level.

I suspect the life expectancy of the compressors on the transition systems (1996-1999) will be lower than those of late.

I have been hearing some good things about a synthetic oil called Ice-32. You may want to research it.
Reply With Quote
Old 09-23-2003, 12:00 PM
jbaj007's Avatar
Registered User
Join Date: Jun 2001
Location: Santa Monica, CA
Posts: 2,053
Hygroscopic means affinity for moisture, although some (even experts) use , incorrectly.

Agroscopic = an affinity for farm produce?

Just joking around.

The hygroscopic oils hold moisture that creates some pretty interesting acids that can lead to pinholes in the evaporator (think of the dreaded 140 evap.).

#1 cause of compressor failure according to one article in a MACS? publication is lack of oil.
The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)
Reply With Quote
Old 09-24-2003, 01:11 PM
MrCjames's Avatar
California Dreaming
Join Date: Jun 2003
Location: SF Bay Area
Posts: 599
I knew I forgot to use the correct term thanks for correcting me.

Avoid those farm products when ever possible!!
Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 04:35 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page