ML55CLA45

my ac compressor just crapped out after 29 years and 110k miles. my mb indep mech suggest converting the whole thing to r134... new compress new everything (whatever that maybe) for $900ish....

just wondering if anyone here has done it..... car run any different?

ill search the other forums but this one was my first stop...

thanks

ohlord

http://www.autohausaz.com/search/pro...C%20Compressor
new drier,new lines ,the old ones will be contaminated flush everything that can not be removed,parts labor and r134a fill at $900 seems a bit high.If he installs an electric fan for the condenser it still seems high.Get some quotes from an a/c place.Very little change my 99 blows 38f air at idle on a hot day on low.

POS

Actually, I think $900 is about right for a new system. The w123s never cooled all that well with the R12 systems (at least not here in Texas), so going to a R134 system would make it even less cool.

You may do as you wish for Missouri, but I like all my old Benzes to have the R12 - it doesn't cost that much more than the R134 when you add up the total bill.

cheapold280CE

why not try freeze 12, I heard it acts just like R12 so you don't have to change all the components just do some cleaning.

check out this page
http://www.dieselgiant.com/repairyourac.htm

You will never get 38 degrees with R134 unless you change your condensor to a more effective one.

240D 3.0T

Freeze 12 is nothing more than 80% R-134a and 20% HCFC-142b. Its still not completely compatible with R-12's mineral oil.

tanktube67

lets see compressor, drier, expansion valve, flush the system the R134 Freon and labor for $900,00 sounds about right,

tanktube67

If I were you, I would replaced the a/c hoses 2

Benzguy604

I have done the conversion a couple of years ago.And all I replaced was the high and low pressure valves on each hose.I never had a problem with the A/C since this retro fit,my pressure is stable and of course no leaks! and plenty of COLD air.
This was done on my 1983 126.
Regards
Big Dan
Vancouver Canada Eh!

tanktube67

I have done the same thing on some of my cars

dogbite5150

I've taken courses in auto HVAC repair.

I've added r134 to an empty r-12 system before and it worked. However....

If you have access to equipment you could pull a vacuum on the system and try to pull the ester oil out of the system. That will also pull the moisture out of the system. 20 minutes minimum.

Flushing could also be done, but that is probably unnessecary.

You can buy 134a with pag oil in it (usually in those conversion kits) or just add pag oil to the system prior to charging. You'll never get every ounce of ester oil out of it. You can keep track of the oil that comes out and add roughly the same amount of pag.

As far as "converting" all you really do is use the fittings so you can add 134a.

One thing to consider. Hoses designed for r-12 will ordinarily leak 134 because the 134 molecules are smaller, but because the system had r-12 in it. The hoses are coated with oil and r-12 molecules, thus preventing leakage. If you flush....well you might get leakage.

dogbite5150

Of course if there are mechanical issues in the system that is the expensive part