Climate control retrofit. - PeachParts Mercedes-Benz Forum

babyjames · #1 02-28-2006, 11:34 PM

I'm going to remove the auto climate control from a 300D and replace it with the manual system from my 240D. Anybody done this? I'm just going to swap the entire heater box/cores. Looks pretty straightforward????

Jay.

Diesel Giant · #2 03-01-2006, 05:44 AM

It should drop right in. I think that is an excellent idea. You will not have any more stinking problems if you do that!

chocolatesoup · #3 03-01-2006, 08:30 AM

i was thinking about somehow re-doing the climate control. i just looked up the what years were the manual systems in place, maybe i will do the same. how much work is this looking like? keep us updated? so youll have to change out the ccu with a manual one, and change the heater core?

lietuviai · #4 03-01-2006, 04:51 PM

I love the manual system in my 230CE! Mine came stock and it is far better than the automatic crap system. You can actually adjust airflow to the front w/s to defrost it without needing to turn on the A/C and have it blow with hurricane force. I think there are almost an infinite amount of combinations of air flow you can adjust. Also mine has separate heat controls for either driver or passenger.

babyjames · #5 03-01-2006, 04:54 PM

Basically its just a matter of removing all the auto crap, and dropping in the manual cc system. Everything but the coolant valves is attached to the heater box (which encloses the heater cores). I think it will take longer to get the old stuff off than anything else. All those vacuum lines ('79 sedan)!

Jay.

Diesel Giant · #6 03-01-2006, 06:17 PM

Its amazing how lazy people get wanting everything automatic. I like manual stuff except transmissons.

babyjames · #7 03-01-2006, 09:27 PM

Why did Mercedes feel it was necessary to add all that stuff for the Yanks? I love my Euro cars, 'cause they are super basic. My 300D will last as long as replacement parts are available (hopefully until we've found a way to get rid of private motor vehicles entirely)!

Jay.

R Leo · #8 03-01-2006, 09:45 PM

Quote:

Originally Posted by Diesel Giant

It should drop right in.

That's like saying all you need to go to Mars is a rocket.

Success on this project will require a donor car to swipe ALL the parts from and, removing the dash from the car with the ACC. FWIW, I've accumulated all the parts to do this same thing but quail at the idea of pulling the dash on my wagon. It will be done one of these days.

lietuviai · #9 03-01-2006, 09:55 PM

Pulling the dash is not that difficult. In fact it is almost easy. There are only a few bolts that attach it and removal can be done with simple hand tools. I've done it and it didn't take very long. Re-installing is only slightly harder than pulling it. The hardest part I would say was trying to realign the center vents and defroster ducts. Everything else was as easy as the removal.

bravohotel · #10 03-01-2006, 11:54 PM

Hey guys,

Do you think that this could be done to 126 SD? Are the "guts" of the HVAC the same between the 123's and 126's? I would love to ditch the auto crap-controller...

Brian

R Leo · #11 03-02-2006, 12:34 AM

Quote:

Originally Posted by lietuviai

Pulling the dash is not that difficult.

That's what dmorrison sez too. But first, I have to pull the dash on my 126...methinks the evap is leaking.

boneheaddoctor · #12 03-02-2006, 09:32 AM

I would think pulling the dash is the easy part......its putting it back together correctly thats a royal pain.

dmorrison · #13 03-02-2006, 11:10 AM

A couple of thoughts. Since I have pulled the evaporator box on both the 82 300TD and the 83 240D, the thoughts off the top of my head.

At the fire wall.
The mono valve and hoses will have to be swapped. control cables installed. Electrical control for the heater water pump.
Hose fittings for supply and return water supply.

The heater box.
Should bolt right in. fitting to vents should be fine. Your center vents can remain as in the 300D. Just block the center vent door open on the 240D box. AC lines, heater lines all OK.
Electrical connections-- figure out the schematics and make sure all connections are accounted for.

Center console. You will need the parts for the AC controls from the 240D they should fit with no problems. Electrical connections to compressor will have to be addressed.

This should be a doable job, but of course somethings will have to be figured out. You should open the evaporator box to the 240D and check everything. Consider a new evaporator core, you don't want to do this again if you don't have to. I'm not inclined to replace the heater core, you can seal it with leak stop if there is a problem.

I have pictures of about 90% of the jobs on both the 300TD and the 240D removal. PM me your address and I will send you a CD with both photo files. ONLY if you take pictures along the way so the next person trying this can consult with you..

Again as Posted you will need a complete 240D donor car for parts.

R Leo, It is a big job but doable. The second time ( the 240D) was easier. If you want the pictures, PM me with your address. The 240D pictorial is much more complete. I knew what I was doing that time and what to photograph.

Dave

babyjames · #14 03-03-2006, 11:38 PM

So, Dave, did you just run the hot wire for the blower motor straigh from the fuse box (fuse 10 on the wiring diagram)? \

I'm eliminating the air conditioning system, and am trying to keep things as simple as possible.

How about controls lighting; looks like it is all on one harness (that plugged into the blower speed switch). I'm just going to keep that harness intact, and run a jumper to another wire that runs to a bulb. Kind of caveman, but that's how I like things.

Jay.