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 09-20-2023, 09:00 PM
Graham's Avatar
Registered User
 
Join Date: Nov 2004
Location: Ontario, Canada
Posts: 4,457
Hard shift when cold - 85 300D

I have noticed that the shifts on my 85 300D are kind of harsh when engine and transmission are cold. I have recently changed fluid and filter and adjusted the Bowden cable. Shifts when warm seem fine.

Maybe the 50C switchover valve isn't operating? I guess I need to come up with a method of testing!


In this thread, Dennislarock said:
"At a coolant temperature below 50º C, a temperature switch (#20) cuts off vacuum signal from the VCV at a Switchover Valve (#125) on the diagram. The vacuum in the circuit produces a higher vacuum to the transducer from a direct line to the vacuum pump (#76) (Should be 67?). Then this higher vacuum is sent to the modulator softening the shifts while the engine is cold.
When the coolant temperature rises above 50º C, the switchover valve is powered on and the VCV controls the transducer."



__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5

Last edited by Graham; 09-22-2023 at 09:39 AM.
Reply With Quote
  #2  
Old 09-22-2023, 09:59 AM
Graham's Avatar
Registered User
 
Join Date: Nov 2004
Location: Ontario, Canada
Posts: 4,457
Can anyone tell me where the 50C temperature switch is located on an 85 300D? It is #20 in diagram.

I see the wires leaving the switchover valve #125 that is near the brake booster, but wires are hard to follow!

__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5
Reply With Quote
Reply

Bookmarks


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 02:18 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page