My 240D has no aux fan (will replace Sat -- was aftermarket already), and has been changed to 134. It is a Euro -- I don't know how much difference that makes in AC systems -- but I just had it in an AC shop which thought the whole AC was aftermarket (?), and offered no solutions to the problem -- which is cold but not cold enough to cool the car (in southern FLA). The compressor is a Sanden; they said it is working fine & the system is full of 134. The fan only works on high but they've never seen the switch & are hesitant to change it out for fear of it "taking a long time to figure out the wiring", for which they would have to charge.

I have read a lot in the archives & know it is recommended to return the car to R12. The shop quoted $500 to do that, incl flushing, etc. I thought it would be a good idea to change to a parallel flow condenser in any case, to improve a system that I think would have been marginal in Florida when new.

1. What are the difficulties with hose connections to parallel flow condensors I read about -- I didn't understand that (seems like I could probably use new hoses by now, anyhow)? Have people had good experiences with the shops that make the hoses (Texas?)

2. Do Euro 240Ds have vacuum -controlled vents in the dash? I have levers, not buttons. I read a post about modifying a CC system to shut off fresh air, & would like to do that with mine if possible -- I can open a window for fresh air.

3. Is there a placement of my 3 slides which opens up fresh air intake ? I have no manual -- maybe I've got it set wrong to start with.

4. How do I identify whether or not I have an R12 expansion valve left in place or a 134 one installed when the changeover was done? If I go back to R12 I will need the correct one & the shop seems to have no clue.

Thanks, as always, for your kind help.

Ed

I can only commen on question No2. Euro 123's have no vacume air vents in the dash. It's all manually controlled from the three slide levers you mentioned.

- Peter.

__________________
2021 Chevrolet Spark
Formerly...
2000 GMC Sonoma
1981 240D 4spd stick. 347000 miles. Deceased Feb 14 2021
2002 Kia Rio. Worst crap on four wheels
1981 240D 4spd stick. 389000 miles.
1984 123 200
1979 116 280S
1972 Cadillac Sedan DeVille
1971 108 280S

the levers are normal in a 240. second, it is quite possible that it is some kind of aftermarket deal. a sanden is def not factory. they were delco in later years and york in early. not many euros had ac, i think. if it is aftermarket then it may not have ever been r 12.

no vacuum sillyness in a 240. try to get some more info and come back so we can help more. i suggest trying to find someone who has a same year us 240 and look at it and figure out everything. i have a euro spec manual for it but it is in german! yaaavourgh!.

good luck

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.

I was told that the vast majority of the air conditioners on our 80-85 Mercedes were installed in the US as a matter of complying with some trade agreement ... or some extraneous factor like that.... and I know that the AC manual for my 240 lists all the hoses as having American threads...
Whether you consider this ' aftermarket' installation I don't know. But it sure may mean different components were used on the same cars in the states compared to Europe.

never heard the story about being installed here. but if done by the dealer or mercedes network i would not consider that "aftermarket". he doesnt say what year. the 123 would not take one of the underdash units.

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.

I have two Euro 240D's both with aftermarket a/c and both with the sanden compressor. These are not dealer or manufacturer connected in any way. It is a very good system, but I would not want to think about running one in the South converted to 134. The capacity is enough with R12 but not enough for 134. You could reverse convert cheaper than you could put in a parallal flow condensor and you would have a better system.

Although it is aftermarket, the ducts and switches are similar to factory components and some components such as the r/d and aux fan are the same as factory, at least on my systems.

Good luck,

Thanks for the replies ......

My system doesn't LOOK aftermarket to me; brackets for compressor look factory to my untutored eye ..... I guess the item that threw me off the most was the evaporator, which is in the dash --- I assumed that spelled factory.

Larry -- the parallel flow condenser was listed around $85 -- are the hoses quite expensive? (My thought was to get a better kind of condenser since I probably a new one anyhow --- radiator just started leaking). I'd rather pay a bit more up front & end up with a better system if I can -- I've moved into real estate & I need good AC for when I ferry people around --- I'd rather not have to buy something mundane and boring to get reliable AC.

The car was originally sold in France -- but I don't know whether the AC was installed there or here.

Anybody know the part # for an R12 expansion valve?

Thanks again ...

Ed

First off if you want to pay a little more to have a better air conditioner then go with R12. R134 has less cooling capacity.

The expansion valve in your system is the same as a factory unit.

There have been many aftermarket a/c systems that are not underdash units. Yours is one of them. The compressor mounting might look factory, but I assure you that it is not.

I am very fortunate that my parts car has a complete and working a/c. The only part of the system that is not a standard part of some sort is the evaporator. Everything else is aftermarket standard and can be bought from places like a/c kits.

The Sanden is a very good compressor. If you run it with R12 it will probably last forever. Changing to 134 raises the high side pressure thus straining the compressor and other high side components.

Good luck,

I am planning to change back to R12 AND add a parallel flow condenser ----- with as much capacity as will fit ....... One of the posts in the AC archives is by a member who had a MB and an older TBird ----- he was struck by how much better the T-Bird system cooled, and the only difference he could see was that the T-Bird had a much bigger condenser. I believe both cars ran R12. So, I concluded that a parallel flow condenser of greater capacity would be a simple upgrade to a system operating in a tough environment.

Anybody have any words of wisdom for replacing the fan switch which only works on high? The AC shop threw up its hands at that one, too -- must look different from the 300D switches they see -- a lot of 123s around, & I see them in this shop ....

Ed

The fan switch is probably not the trouble. It is the resistor pack that is mounted near the motor.

If a car does not have enough condensor capacity, then increasing it will obviously help. On a car that already has enough, then it will be a waste of time and money. There is a point you reach where added capacity does you no good. You will know if you are at this point because you already are getting the evap as cold as you can get it without freezing up.

Good luck,