w140 : Replacing Compressor, possibly Evaporator
 

I have decided that Im going to get my AC fixed before the heat hits here in TX. I already know that my compressor is bad(it seized up a few weeks ago), and have been able to find a rebuilt one for $475.00.

I also managed to enlist the help of a benz mechanic that works for a good independent shop here in Austin, ********. What I want to know is I we do put the compressor and find out that the evaporator is bad...what is the going price on this part?

I priced it at Benz Bin, and for a 94 S320, it has two evaporators listed, one for 186 and one for 220.00. From my search of the posts, most seem to think that the evaporator is around 650...

Also, is there anything else i should have done at the same time these repl's are being done? I already plan on having him change out a few dash bulbs that are out...while the entire dash is in pieces.

Thanks

As long as there was no leak in the evaporator, there should be no need to do these both at the same time.

The main thing, since the compressor is being replaced due to seizure, is to THOROUGHLY FLUSH the system. You will need to flush, Flush and FLUSH! Any particulate left in the system will find its way back to the compressor and destroy it.

Also, you can go to an auto a/c supplier and get a suction side filter, which is sometimes only a screen. This goes in the line at the suction side of the compressor. DO NOT RELY ON THE FILTER DRIER FOR THIS PURPOSE. There is lots of volume after the filter drier from which junk could come and destroy your new compressor.

So, to summarize; flush the system thoroughly, replace the filter drier, see that the correct amount of oil is in the compressor, use a suction side filter and evacuate thoroughly before charging.

Good luck,

PS: Did I remember to say something about how important it is to thoroughly flush the system after compressor seizure? LB

If possible, return the rebuilt unit for a refund, and buy a new UNICLA brand compressor. It should about the same cost, or less.
http://www.ackits.com/ is a source. If you ever disassemble your defective unit, you will see all the wearing surfaces that may, or not be, resurfaced by a rebuilder. There are no industry standards for rebuilding compressors.

Replacement of the evaporator is a MAJOR job. Some models have something like 22 hour labors as the flat rate.

The Unicla compressoors are nice but you will never buy any parts for them. I used a few untill I had a problem with their Micky Mouse speed sensor arrangement on one.

I got so burned in the eighties with rebuilt Nippondenso compressors that we quit using anything but new untill MB came out with their own rebuilts. Now Behr is offering them and I have used them also. We have problems even with the MB units but only with leaks.

I wish you luck with your back yard expedition. I wouldn't do the evap unless clear indication of failure. There is virtually no overlap in doing the two jobs except for the evacuation and recharging. The cost of R134 and recharging is small compared to the costs and risks of doing the evap especially when done by a tech who can't answer these questions.

The difference in price has to do with what you buy. Its sort of like buying diamonds, there is more than just shine and size to be considered. The high price you quoted is for a Mercedes-Benz evap. The others aren't. Just like the compressor though, a reasonable facsimile can be had at great savings.

All of these factors and some skilled labor are the reasons many people use professionals and since I give my time freely here I every once in a while throw in editorial comment!

I have helped thousands fix their own cars, but I feel the use of a quote "benz mechanic" out the back door of an establishment gives many an unrealistic view of the costs of auto repair. That quote "mechanic" is likely paying no taxes and many of the other necessities of auto repair. I used to blame the tech but now understand there is a great segment of society that doesn't give a hoot about the environment, health care, or other rules and regs. It is real convenient for those people to let some "mechanic" short change all those elements and of course its his fault none of those "costs of business" got on the bill.

The word slacker comes to mind. Use it where it applies.

Backyard Mechanics
 

Steve, I can see what you are saying about getting a mechanic to do it on the side. I know that employee loyalty is part of it, but I do like to shop around just like the next guy. If I can get the job done for hundreds less, Im all for it. Kind of like telling all of these DIY'ers not to bother trying to save money doing it themselves...and that only a mechanic employed by the dealer is authorized or should be authorized to do it...kind of Nazi regime if you ask me.

I am a novice when it comes to cars...but I do have substantial skills when it comes to computers. In fact, I make my company hundreds of dollars an hour for network fixes and installs, and travel the country to help businesses get their networks up and running, or to fix problems that hurt productivity...I have seen the amounts charged for my expertise, installs per computer range anywhere depending on complexity from 90 to 500 dollars.... and when you are installing anywhere from 25 to 1000, it quickly adds up to hundreds of thousands of dollars. I dont expect anything more than my salary, which is adequate.

Of course, I too have used this knowledge on my own time...And thats what I see it as, my time. Sometimes i do it for free, sometimes by barter, and sometimes for a little extra money. This forum is a great resource for DIY'ers, and it has been helpful. Is altruism dead? I wouldnt go that far. But I wouldnt also go as far as saying that one shouldnt consider all options. I dont see any reason to knock these guys or the people that enlist them.

AC is done! Cold as ice!
 

Just thought I would post something to end this thread. I always read threads from other members, and it seems that they just end abruptly...I guess cause they get enough info and get the info they need.

I got my car back on Saturday. The AC is cold....and I mean real cold...I guess these w140's have one heck of an A/C system if you iron out all the kinks. I bought a used compressor from Greenleaf for $260.00. The receiver/dryer was 52.00, and I also replaced the drivers side tie rod(upper and lower $68.95), and put new PBR brake pads(31.00) on front....

My car is running great...although I am going to have to take the car in for an alignment, and the steering wheel is a little cockeyed now.

The next thing on my list will be the drivers side seat belt, which is frozen solid...and my headrests, which are also dead...The rest of the car seems fine...

Thanks again to everyones input...and I hope that I can return the favor in the future to the newbies and future w140 owners out there.

It has been 4 years now. How has the rebuilt compressor from Greenleaf held up?

-Jim