Thought I would share some good news!

Well I bit the bullet and decided to get the AC going in the 89 300SE. It was not functioning when I bought it and had not worked the whole time the previous owner had it for 5+ years. Last year I took it to a local indi MB shop and had him try to make it work. He was able to charge it but said that I had high preasure on the low side and probably an obstruction. So he evacuated it and I went without AC till the first of July this year. I got the following new parts:

Compressor (Denso Factory Remanufactured)
Expansion Block/Valve (the Eghoff from here)
Receiver/Dryer
High and Low preasure switches on R/D
Set of new O rings for all of the hoses.
New Aux electric fan (ACM brand)

Started by taking off the expansion valve, compressor and opening all the lines. Flushed the Evaporator, Condensor and all the lines (except the run with the muffler). I used the Napa DuraFlush II and got the most of the dirty flush fluid from the evaporator with a few bits of black stuff. A few aluminum shavings from the condensor. Flushed the Evap 6 times with the flow and against. Condensor 3 times and hoses 2 times. Buttoned it all back up with oil in the evap and new compressor and pulled a vaccum on the system without the Receiver/Dryer on it but the lines joined together with a hose. Held that vacuum for 4 hours using the pump. Installed the new receiver dryer and vacuumed that down for another 2. Crossed my fingers and took it back to the indi shop and had him charge it up. He added more oil to it while charging it with R12 and its now functioning great! Cools the car down nicely in 85 degree weather. Our summer has been unseasonably cool here so no 95 degree plus test yet. Over all I am happy with it and its very nice to have it work.

Over all it was not too bad getting the expansion valve off the W126. Its just tight. You can almost do it without crows foot wrenches but its hard to do. I used some chineese wrenches and the shape of them is wrong. You need a more rounded head instead of a traditional open end wrench shaped head. I took about 2 weeks to do the job with ordering a few more parts including a new belt. Took my time on it instead of rushing. If you have been putting this job off and can spend the money on I encourage you to do it yourself. This was my first AC job and while I did not charge (yes I chickened out) it I did most everything else and saved some $$ on labor. Did a lot of reading on the forum and would like to thank everyone that has contributed to the forum for the help!

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1989 300SE - Siegfried
2010 Toyota Tundra Crewmax
2005 Honda CRV

Gone but not forgotten
2001 F150 Supercrew - The Screw
1966 Ford LTD 390 - The Big G!
1995 Mercury sable
1986 Subaru DL
1982 Ford EXP - my first car