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 > Tech Help

LinkBack Thread Tools Display Modes
Old 08-02-2016, 11:38 PM
Registered User
Join Date: Jun 2011
Location: I now live in Northern Virginia and intend to stay for good.
Posts: 15
Mono valve part 1984 300d turbo w123

I've searched the entire site and have not found the "mono valve".
I have bought an after market part made in China and it failed to function.
I heard that the genuine Bosch mono valve is no longer available.
Can you suggest where I can find this part?

Reply With Quote
Old 08-03-2016, 11:07 AM
Registered User
Join Date: Mar 2003
Location: Southern California
Posts: 2,165
By "mono valve" are you referring to the vacuum operated on/off coolant flow control valve to the heater core that's located underneath the HVAC air inlet screen below the base of the windshield on the passenger side?

Reply With Quote
Old 08-03-2016, 11:39 AM
Registered User
Join Date: Nov 2015
Posts: 687
On an '84, I believe the monovalve is electronically activated (my '85 is). One option is to find one in the junkyard, even if the diaphragm is torn. You can use the diaphragm from the rebuild kit you bought on the junkyard one. I haven't found markings on any of the (several) that I have sourced, but I believe that the aftermarket part has a higher polished solenoid housing, while the original Bosch ones are more of a matte finish. You might grab several if there are multiple donors at the junkyard, I've had to swap between a couple different ones until I found one that (seems to) work well.

Another option is to contact George Murphy from this forum, he may have some rebuilt units available.
'85 300D - federal spec, built in late 84. 85 300D Complete AC System Rebuild
Reply With Quote
Old 08-03-2016, 12:14 PM
Registered User
Join Date: Sep 2013
Location: Alhambra California
Posts: 2,731
The monovalve repair kits are iffy because quite often the electromagnet in the monovalve is defective which the repair kit does not address.

Last edited by BWhitmore; 08-03-2016 at 09:53 PM.
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 07:29 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2021, 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