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-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 07-13-2008, 11:32 AM
oso oso is offline
'87 300TD
 
Join Date: Oct 2007
Location: San Antonio, TX
Posts: 189
a/c question

Yesterday I had a guy tell me he could fix my a/c problem: compressor shutting of after a few minutes. He said it would need the expansion valve flush. I have the '87 300TDT and freon level or belt slipping are not the usual suspects.
Reply With Quote
  #2  
Old 07-13-2008, 11:41 AM
Registered User
 
Join Date: Sep 2004
Posts: 8,636
Does the a/c operate normally for 5-10 minutes, then the compressor disengage and not come back on for an extended period?
Reply With Quote
  #3  
Old 07-13-2008, 11:45 AM
oso oso is offline
'87 300TD
 
Join Date: Oct 2007
Location: San Antonio, TX
Posts: 189
Quote:
Originally Posted by tangofox007 View Post
Does the a/c operate normally for 5-10 minutes, then the compressor disengage and not come back on for an extended period?
Correct.
Reply With Quote
  #4  
Old 07-13-2008, 11:57 AM
Registered User
 
Join Date: Sep 2004
Posts: 8,636
Then I would suspect the evaporator temp regulator. It is supposed to disengage the compressor to prevent evaporator freeze-up, but it can fail so that it "trips" at a too-high temp. You could unplug it and jumper the plug and see if that solves your problem.
Reply With Quote
  #5  
Old 07-13-2008, 03:49 PM
sixto's Avatar
smoke gets in your eyes
 
Join Date: Jun 2000
Location: SF Bay Area
Posts: 20,759
Could also be a temperamental Klima relay or low pressure switch.

Sixto
87 300D
Reply With Quote
  #6  
Old 07-14-2008, 10:22 AM
oso oso is offline
'87 300TD
 
Join Date: Oct 2007
Location: San Antonio, TX
Posts: 189
Quote:
Originally Posted by sixto View Post
Could also be a temperamental Klima relay or low pressure switch.

Sixto
87 300D
No easy way out, as always....
Reply With Quote
  #7  
Old 08-23-2008, 04:11 PM
oso oso is offline
'87 300TD
 
Join Date: Oct 2007
Location: San Antonio, TX
Posts: 189
Quote:
Originally Posted by sixto View Post
Could also be a temperamental Klima relay or low pressure switch.

Sixto
87 300D
Today I broke down and bought a new KLIMA relay- you were right on with the guess regarding a "temperamental" relay! Just a side observation: after I had a new unit in and a/c blowing cold air, I decided to take a look at the old one. It looked like it may have a darker spot on the board: how could it have happen with just 12v passing through?
Reply With Quote
  #8  
Old 08-24-2008, 01:53 AM
compress ignite's Avatar
Drone aspiring to Serfdom
 
Join Date: Feb 2004
Location: 32(degrees) North by 81(degrees) West
Posts: 5,554
Don't DO This !

12Volts D.C. ain't anything like A.C...12 volts D.C. will stop your heart!
12 volts D.C. is enough power to weld a wrench dropped so that it contacts
both poles...
12 volts D.C. will turn the tip of a glow plug so cherry red that you can brand
cattle with it for about 5 minutes (AFTER it's disconnected).

Think about it this way: Alternating Current switches Polarity back and forth.
Direct Current is just straight power...
__________________
'84 300SD sold
124.128
Reply With Quote
  #9  
Old 08-24-2008, 11:17 PM
oso oso is offline
'87 300TD
 
Join Date: Oct 2007
Location: San Antonio, TX
Posts: 189
Thanks to "compress ignite" another lesson learned! Hopefully you'll be around for many more of my "how come...." posts. Appreciate the straight up help.
Reply With Quote
Reply

Bookmarks

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 12:16 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, 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