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 03-10-2002, 01:53 PM
C. Mariscal
Posts: n/a
450 slc heater always on

I have a 1975 450 slc, and the heater won't turn off. Is something else wrong other than the heater? It also runs sluggish...

Thanks C.M.
Reply With Quote
Old 03-10-2002, 02:24 PM
Posts: n/a
I had the same heater problem. It was the monovalve, I think its called. At any rate, its a valve that sits in front of the heater blower cover in the engine compartment. It was a couple of hundred dollars or so to get it replaced. I was also told that sometimes the control levers get stuck in the on position, and that this is a major hassle to fix.
Reply With Quote
Old 03-10-2002, 08:03 PM
steven renick
Posts: n/a

micro-switches on heater controles
If the car has eletronic fuel inj. it probibly has the old style slides in the console.These work vac. switches that turn off the hot water.
The defroster doors stick letting a/c air fog the windshield,major repairs in store.
A manual valve installed at the firewall will help.
Reply With Quote
Old 03-11-2002, 11:07 AM
C. Mariscal
Posts: n/a
Thanks for the info.

C. Mariscal
Reply With Quote
Old 03-11-2002, 11:49 PM
Registered User
Join Date: Jul 1999
Location: Los Angeles, Ca.
Posts: 21

If you paid a couple hundred bucks to replace the heater valve, as you described, get a new mechanic. These valves are about $40, take less than 30 minutes to replace and the job is easy for a do-it-yourself'er.

Steve Guilford
107 026 12 000677
Reply With Quote
Old 03-15-2002, 02:19 AM
Registered User
Join Date: Mar 2002
Location: Texas
Posts: 38
I need this done on my car, thanks for the info. I won't be doing it myself and it is good to know how much it should cost!
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

Similar Threads
Thread Thread Starter Forum Replies Last Post
Very fast Idle, 5.0 in 1980 450 SLC (Euro) Leewolf SL Forum 24 08-02-2013 09:11 PM
Somewhat rare ? 1979 450 SLC tabasco85331 Vintage Mercedes 3 02-28-2003 04:46 PM
1975 450 SL heater control Doug Wilson Tech Help 1 11-04-2002 08:30 AM
450 SEL engine to a 450 SLC (79s), Problems? Leewolf SL Forum 0 03-04-2002 11:55 PM
Vacuum Diagram for 78 450 SLC Euro please !! mcarboni SL Forum 6 01-22-2002 05:02 PM

All times are GMT -4. The time now is 01:37 PM.

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