can you bolt it right on or is it too small or are there some other complications i am not aware of...thanks, everyone.

AC consists of the whole system. If you are talking of compressor, then yes they should be the same.

(of course this assumes that both are 1980 or later, and have GM R4 compressor at engine front lower left....)

__________________
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 agree.

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

So I will be watching this THREAD closely. I long for the simplicity of the 240D's manual HVAC in comparison with the non-functioning pieces in the 300D now.
Yes, I agree, we need to get specific for I can only speculate that you are probably talking about the components in the console or under the dash... the controls... the evaporator... etc.?

I suppose you could take the P/N(s) for components like the "evap" and compare the two models?

A burning question for me is will the plastic console have to be replaced along with the controls.
Regards,

i think only the face plate.

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

OK this has been discussed, But as a Christmas present.

Yes a manual AC/heater system can be replaced with the auto system or vis versa. BUT BUT BUT.
Consider this.

Assuming your going from auto, the more complicated, to a manual. You have Remove the center console. The dash. The evaporator box the mono valve. See this post for the removal.

http://www.peachparts.com/Wikka/W123Evaporator

Now to make the manual system work.
Put in the manual box with the cables, the manual AC controls in the center dash. Run the cable to the manual heat control valve in the engine compartment that you replaced. Figure out the wire harness so that it will work in the car. Charge the AC system, refill the radiator.

This is a basic idea of what needs to be done. It does not include all the little details that go along with a conversion.

It is a big job.

It's easier to maintain the system installed in your car.


If your thinking of just the controls in the center console. They are controlling items not installed in the auto system. Cables must be run and to a lever that is not setup for the cable. The mono valve must be replaced to the manual valve control, and the cable run through the firewall. It is not a simple swap. The auto system is operating automatic systems. The manual is operating manual controls on the evap box.


Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

whoa...already intimidated, hahaha.

i want to take an a/c (all components) from a 1981 240D and put it into a 1983 240D (with a non a/c 617.952 conversion).

how much could i get a complete aftermarket a/c for otherwise?

how much for a working used system?

thanks, everyone.

If you have both cars there for the job. It will bolt right in. But your completely removing the old and installing the new. A W123 is a W123 and both cars will take all 3 versions of the AC systems Mercedes designed for the W123 over the years.
A 240D to a 240D should be easy. The center AC control switch ( fan switch ) may be different. The AC version has a cable that opens the Ac main flap. That flap should be on the non AC one, but not 100% sure.
Go to the link above, The maroon colored car is the 83 240D Ac setup. All that has to be installed. And removing the center console and dash are required. The wire harness may also be a consideration. Your operating systems related to the AC setup and not just heat. You will have to swap, or install, and wire the temp control dial ( picture # 20 in the link above)

Not sure when the changeover to the dial occurred during the 240D production. that could be a problem to solve.

An aftermarket AC system for a Mercedes, I don't know of any company who builds one. Doesn't mean that it is not out there.

If you have both cars there for the conversion . It will be much easier. But a time consuming task.

Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

The difficulty in making the 240D to 300D Ac swap is the control of the flaps in the evaporator box. The picture below shows the difference between the 240D , on the left, with the 300TD evaporator box. Both levers, one controlled by the cable and the other by the vacuum element. Are controlling the same flap in the evaporator box. Converting without changing the evap box is not possible. No place to clip the cable to, and the lever is a different shape and length. The cable would not throw sufficiently to do the job. All the vacuum elements are setup this way except the recirculation flap. They are identical between the 240D and 300TD.

Additionally the 240D AC controls attach to a U shaped bracket that is pop riveted to the console side of the evaporator box. This must be there to hold the AC controls in the 240D. The 300D does not have this bracket. It is available from Germany. But where to pop rivet it???? and what are you drilling into when pop riveting it.

Dave

Attached Thumbnails

 

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

Sorry I've taken so long to respond to your thoughtful POSTS... but I guess I failed to sign up to receive notices of POSTs on this THREAD. Now I'm signed up.

Needless to say, your obvious knowledge and insight about the difficulties one would face to convert an automatic Heat & A/C in 1 300D to a manual Heat & A/C from a 240D... well let's just say your cautions are sobering and should be heeded!
Thanks,