The 78 has the Servo, it is under the air intake hose and has that bundle of vacuum hoses going to it. the buttons on the dash will be in a verticle set up. and has the York AC Compressor.

The 81 has the Mono valve on the firewall to the right of the battery tray. there is suppose to be a valve that set inside it that controls the water flow to the heater core. the PBU (push button unit) on the dash has the horizonal buttons. the AC compressor is the R-4 that is mounted on the lower left of the engine. the large hose coming from under the battery tray and across the front of the Valve cover will lead you to it. this is one of the AC hoses.

I may be wrong, but don`t believe the R-4 compressor will bolt onto the 78 engine. there may not be the mountings cast on the block for the AC mount bracket.

I was looking at your 83, looks like a Euro, and has the manual climate control system. this is what CFH was mentioning he installed into his. the best system of the three.

MB refers the manual as the type one
The servo as Type two
The one with the Mono valve as Type three

As per the FSM.

If you want to do any swapping of systems, go to PNP and remove the dash and the whole heater/AC box from a 240D. you are looking at around $60+ for one. you will have the Blower, Heater Core and Evaporator. take the box apart, clean the evaporator fins of debris, and the Heater Core. replace the old dry foam seals on the various doors, and you will be good to go.

I have one apart now, and hope to have it in by winter.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works