Author Topic: A/C system replacement  (Read 2650 times)

1974450SEL

  • Enthusiast
  • *
  • Posts: 80
  • Fresh Paint
  • Location: Portland Maine
A/C system replacement
« on: 23 March 2009, 05:31 AM »
Has anyone taken on the challenge of replacing the A/C compressor, expansion valve, evaporator and Receiver/Drier?  I had my car at the repair shop and was told the Compressor is definitely shot and they said it would be about 25 hours labor to remove the entire dash assembly to get to the expansion valve and evap core.  Compressor was a pretty easy change as well as the receiver/drier.  Basically about 2500.00 for everything.  They recommended with the age of the car to replace everything.  This is a reputable place and has done good work for me in the past.   I've replace a heater core in a Ford and that required removal of the dash (what fun that was) so I am thinking next year to do this but she's fine for now till the Summer heat. 

another sad 280s

  • Classic
  • **
  • Posts: 124
  • Location: kyabram, vic
Re: A/C system replacement
« Reply #1 on: 15 April 2009, 06:47 AM »
add another person curious about this. my compressor has been off for years now, so i'm assumong that nearly everything will need to be replaced when it comes time. having said that $2,500 sounds like it may wait a while still.

pez

  • Classic
  • **
  • Posts: 193
  • when they make a better car, I might buy it...
  • Location: denver, colorado, usa
    • Business Profile
Re: A/C system replacement
« Reply #2 on: 15 April 2009, 10:04 AM »
They want to replace the expansion valve as a matter of course, not because there is something wrong with it. Do everything else under the hood and skip the expansion valve. Have them do one or two thorough a/c flushes instead, it will get the expansion valve totally clean.  This will keep them out of tearing the dash apart.
1976 450se Euro Daily Driver....currently 4 sale, moving to Mexico

transilvana

  • Newbie
  • Posts: 14
  • Location: Spain
Re: A/C system replacement
« Reply #3 on: 15 April 2009, 11:31 AM »
You don´t need to remove the dash to get to the expansion valve, it can be done easily. Remove the cover under the steering wheel, also the air cover beneath it. The expansion valve is above the acelerator pedal, in front of the key lock. I´ve just finished the interior restoration on my w116, i replaced everything and took apart the dash so I know where it is. Also you can access removing the dash clocks, would be easier.

But if you want to change the evaporator then you need to remove everything, and I mean everything. this is the photo from my car, take a look inside the dash where the clocks are missing, you will see it on the right side white color





« Last Edit: 15 April 2009, 11:52 AM by transilvana »

WGB

  • W116 Addict
  • ****
  • Posts: 3,280
  • And on the eighth day he made the 116
  • Location: Perth - Western Australia
Re: A/C system replacement
« Reply #4 on: 16 April 2009, 02:00 AM »
If you are converting from F12 to H134a it is better to change the expansion valve.

Easy enough to do as clearly shown in the above photo but getting enough purchase with a spanner in the confines of the binnacle can be difficult..

There should be no reason to change either the evaporator or the condensor on a 450 unless they are damaged. In particular the evaporator is copper and should last a long time unless someone stuffs up..

The compressers are easily available Frigidaire A6's which are not expensive to purchase new (Preferable to recon units).

You will need a receiver-drier ($19 from Autohausaz.com) and there will probably be some hose replacements but they should be manufactured in-house by a competent A/C shop.

I have reconditioned two a 450 and a 6.9 and it is worth doing properly but the dashboard should not need to come out.

Bill

another sad 280s

  • Classic
  • **
  • Posts: 124
  • Location: kyabram, vic
Re: A/C system replacement
« Reply #5 on: 16 April 2009, 05:19 AM »
thanks for that. seems a bit more worthwhile. being a 280s i don't have the value of a $20,000 6.9 that i'm adding to.

bolbol

  • Classic
  • **
  • Posts: 140
Re: A/C system replacement
« Reply #6 on: 17 April 2009, 12:35 AM »
Please see my old poston this topic , I have changed everything on the A/C system ;)
http://forum.w116.org/mechanicals/what-i-have-done-to-get-good-ac-cooling/msg55535/#msg55535

bolbol

WGB

  • W116 Addict
  • ****
  • Posts: 3,280
  • And on the eighth day he made the 116
  • Location: Perth - Western Australia
Re: A/C system replacement
« Reply #7 on: 17 April 2009, 06:08 AM »
thanks for that. seems a bit more worthwhile. being a 280s i don't have the value of a $20,000 6.9 that i'm adding to.

The 280 uses a different compressor and a smaller evaporator to a 450 or a 6.9 and these really need replacement if you change to H134a which probably makes it an even less attractive financial proposition but good working aircon in a hot climate makes the car much more usable - to me anyway.

For interest it cost me $1600 for a new compressor, pipework, TX valve and receiver drier on my 450 three years ago - full professional Aircon Shop - drive in drive out and no problems since.

My 6.9 cost $2100 at the same place a year ago and after the problems with the porous pipe were sorted (by myself) it has been brilliant through a hot summer.

Bill

Hemersam

  • Classic
  • **
  • Posts: 355
  • Location: Dallas, Texas, USA
Re: A/C system replacement
« Reply #8 on: 17 April 2009, 06:24 AM »
The condenser on my '78 280SE is original; is it made of copper or aluminum?
Hemersam

Hemersam

  • Classic
  • **
  • Posts: 355
  • Location: Dallas, Texas, USA
Re: A/C system replacement
« Reply #9 on: 20 April 2009, 06:26 PM »
Copper or aluminum, anyone?
Hemersam

TJ 450

  • W116 Addict
  • ****
  • Posts: 4,140
  • Location: Rockingham, Western Australia
    • Tim's Insulators Downunder
Re: A/C system replacement
« Reply #10 on: 20 April 2009, 08:10 PM »
I would have thought aluminum. The condensers on my cars are aluminum.

Tim
1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
2003 ML500

WGB

  • W116 Addict
  • ****
  • Posts: 3,280
  • And on the eighth day he made the 116
  • Location: Perth - Western Australia
Re: A/C system replacement
« Reply #11 on: 21 April 2009, 01:58 AM »
Condensors (In front of the radiator) always look like aluminium to me - evaporators (in the dash) for 116's were originally copper which is why they give little trouble (Thank God) as getting them out is a crap job.

I know 124's changed to aluminium evaporators and give trouble as they rot from the outside in if kept damp with condensed water on the outside of the fins.

Bill

Big_Richard

  • Guest
Re: A/C system replacement
« Reply #12 on: 21 April 2009, 03:30 AM »
condensor on my 6.9 is aluminium too, which is surprising, since it looks like on the one side with all the half circle pipes joined in, looks like its soldered copper, but it aint!

I didnt know aluminium could be welded in this manner, there are what looks like bulging drops of excess solder at the base of most of these joints. Learn something new everyday.



1974450SEL

  • Enthusiast
  • *
  • Posts: 80
  • Fresh Paint
  • Location: Portland Maine
Re: A/C system replacement
« Reply #13 on: 02 July 2009, 07:45 PM »
Thanks all for the replies, its now hot summer here in VA and the parts are ordered and will be fixed next week by a dealer for a reasonable charge, much less than 2500 even with parts.  Correct on the dash not coming out.  Downloaded the shopmanual, very thankful for this site and  having those on it!  I will look into replacing the interior fan with one from a W126, good suggestion.