Ive got my 80 300SD now and The heat does not work. I popped the hood to check the monovalve i expected to be there (like on my 126) and there is this big box with wires over the lines going the heater core. Can someone explain what this is and tell me if this thing has a monovalve?

Thanks

Sounds like the regulator on an older 123. There is a thermal switch and the heat will not cut on unless the engine coolant is +60deg C. Does the heat come on when you use defrost?

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http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

They are the same. I don't know much about them except they tend to crack and break.

--Matt

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KI6CCA

Current Stable:
1987 300SDL
1980 450SEL

Out to Pasture:
1982 300D KIA (Rice Rocket vs. 123: He hit me at 80-100MPH I walked away he went to the hospital. Sounds fair to me!)
1985 300D EURO Scrapped (got more money from state than car was worth)
1979 & 1980 300SD Great Cars!

That is whats known as the Climate Control Servo, they are notorious for failing/cracking, the usualy solution is to replace it with a rebuilt one, they cost $200-300. Others may chime in with other ideas...

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Performance Products sells an electronic replacement for old climate control eliminating a lot of the problems. You might want to ping people on the forum about it.

I replaced mine with an aluminum cast one for $495. The electronic replacement came out years later.

Just a thought....

http://www.performanceproducts4benz.com/productpage.aspx?pid=109850&name=Digital+AC+Servo+Upgrade+Kit


and the manual to install:

http://content.************************/instructions/ACCIIControllerManualRevH1.pdf

I'm not sure how to post a link but if you do a search for "300SD heater woes" you will find instructions on how to get heat for this winter. I think the post is on pg. 5 on this forum all will be well.
Regards

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2dieseljohn
1979 300sd (283,000+) Road Trips
1983 240D 4-speed (350,000+) Daily Driver
1967 E-TypeS1 in bits and pieces

I also replaced the servo on my 77 with an aluminum bodied version. I don't know if the new electronic one is a better choice or not. I don't recall seeing any posts on this forum by someone who has installed it. We're all probably jsut too cheap.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

No, that is what's know as "The EVIL Climate Control Servo"........

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Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

I confirm:
Congratulations you had your first look at the dreaded Chrysler (yes as in Chrysler the now other brand of DCX) Automatic Climate control Servo (ACCII).

BTW, I already buzzed this forum several time about the Digital replacement ... and nobody ever answered (and i posted it, in the tech, diesel, SL, G, and vintage section...).

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Aquilae non capunt muscas! (Eagles don't hunt flies!)


1979 300SD Black/Black MBtex239000mi
1983 300TD euro-NA. White/Olive Cloth-MBtex 201000mi. Fleet car of the USA embassy in Morocco
1983 240D Labrador Blue/Blue MBtex 161000mi

BTW
Our Fastlane friends seem now to be one of only too distributors for the ACC retrofit:
http://catalog.peachparts.com/item.wws?qty=1&mfr=UNW&sku=ACC2G04

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Aquilae non capunt muscas! (Eagles don't hunt flies!)


1979 300SD Black/Black MBtex239000mi
1983 300TD euro-NA. White/Olive Cloth-MBtex 201000mi. Fleet car of the USA embassy in Morocco
1983 240D Labrador Blue/Blue MBtex 161000mi