I am changing out everything between the condensor and evaporator on my mom's 85 300sd. Ordered all the hoses and parts had them shipped to Canada. I called an MB dealer in Ft Worth who told me the suction line from the expansion valve to the top of the fender was a steel line. Now that I am looking at the car I see that its another rubber hose through the firewall. Nobody lists it on any parts website. How crucial would it be to change that section of suction hose? Could an A/C guru make up a line using the existing ends? How hard is it to replace that section?

Yes that is possible. Sorry, I am not sure how hard it is on an SD. But someone should be able to tell ya.

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1983 123.133 California
- GreaseCar Veg System

Why are you changing out the lines?

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Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?

As long as they would add one additional commandment for you to keep thy religion to thyself.
George Carlin (Wonder where he is now..)

1981 240d (engine donor 1983 240d) recently rebuilt engine hurray! - No more.. fought a tree and the tree won.

pearl black 1983 240d 4speed (Converted!@$$%) atleast the tranny was rebuilt.

Well to answer my own question the suction line from the expansion valve to the top of the fender is a real bear to get at (getting the oval firewall gromment properly seated). The A/C folks could not weld any appropriate ferrels onto it so they could not make up a new hose. They were confident with the condition of the old 23 year hose, and I stuck it back in (126 830 06 15 available from MB only) Could a hydraulics shop have made it up? I don't know. Everything else between the condenser and evaporator was replaced. Aligning the expansion valve so you don't x thread the fittings proved very challenging (not much wiggle room) When replacing the compressor I found it helpful to attach the hoses first, and feed the lines up from the bottom. You can hang the compressor on an engine bracket by the metal ferrels while you fiddle the bolts and spacers back in, easy. System charged with 41oz R134a, (89%) yielded 10C/52F at center vent with an OAT 26C/79F , not great but good enough for Canadian summers. R12 is not even an option in Canada.
You do not need to remove the instrument cluster in order to remove the crash bar covering the exp valve, as this 85 did not have one. Check the accessability of your expansion valve first. Fittings on exp. valve are 19mm and 22mm crowsfoot. (Craftsman worked just fine)

Markus, You should be doing much better (cooler) than 52f with R134a in an 85 SD. I have seen <40f in mine with OAT much higher than you have.
How many tube does the condensor have? Some 85 W126s have the 50 tube condensor. Works well with 134a.

Yea, I've felt the AC fury that Dan's '85 SD throws down and it is downright frigid! Very cool looking condenser....

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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

Up until yesterday... She's not cooling nearly as good for some reason. I suspect there's a leak in the system somewhere.

What did you touch the other day when we had the hood up?

I loosened the schrader valve in your counterfeit high side cap......
Least I could do since you were giving me a radiator and feeding me too!

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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 should have poured SLS fluid under the rear of your wagon.