Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #151  
Old 07-12-2011, 08:41 PM
Registered User
 
Join Date: Sep 2001
Location: central Texas
Posts: 17,281
I would use a standard flushing fluid myself to make sure I avoided any residue which might cause problems later...
The MB AC manual is very specific about the whole procedure.. even specifying which direction to run the fluid through the disconnected hoses....

Reply With Quote
  #152  
Old 07-12-2011, 10:42 PM
Registered User
 
Join Date: Jul 2005
Posts: 81
Is the MB flush procedure available on this site somewhere?
Reply With Quote
  #153  
Old 07-16-2011, 06:34 PM
remotemark's Avatar
Geplatzt
 
Join Date: Aug 2007
Location: Philadelphia
Posts: 1,018
Did the reverse conversion. Forty degree vents today with 85-90 ambient. I'm pretty happy! If I could figure out how to degrime evap fins, i'd probably be even happier.

Quote:
Originally Posted by remotemark View Post
I'm sick of the crappy cooling I get from the 134 in my 84 W123 300D. In the shade or on a cool morning, I can get 55-60 degree air from the vents, but when it's hot here in Charm City, I'm lucky to get mid-70s, and when 95 and the muggies hit, it doesn't seem to do much of anything. So I've decided to bite the bullet and do a proper reverse conversion to R12.

I bought some 12 oz. cans of R12 off a fellow on CL ($100 for 16 cans). I've ordered a new R4 compressor, a new condenser (mine has plenty o' bent fins -- maybe 40-50% of them), a new receiver-dryer, and a new high-low switch. Does anything else need replacing to do this right? Any of the hoses?

I've found a good radiator and a/c shop and will ask them to do the following for me: 1. get out the 134. 2. hook up the hoses to their flushing rig and flush all of the oil out of the hoses and the evaporator as many times as they can. 3. install the new components. 4. pull a vacuum to see if there are any leaks. 5. charge with oil and R12 (I have to supply it for them).

Have I covered all my bases? What is the correct R12 charge for my car?

Thanks!
__________________
I never go far without a little Big Star

1994 E500 199/Gray 82k
84 300D (Salty) Orient Red/Palomino 141k
88 300CE (Ersatzhammer) 904/Java 163k -- Turbo Technics twin turbo kit, AMG Gen I body kit, Sportline steering box and steering wheel, Sportline/Eibach /Bilstein Sport/500E suspension, Quaife LSD in 210 mm diff case, Silver Arrow brakes.
88 300CE Brabus 3.6 199 on Black 44k
Reply With Quote
  #154  
Old 07-16-2011, 06:48 PM
Registered User
 
Join Date: Sep 2001
Location: central Texas
Posts: 17,281
Congratulations.... really glad to hear that...
I have been reading in the MB service manual trying to figure out how to access the evaporator..
Reply With Quote
  #155  
Old 07-22-2011, 11:19 PM
Registered User
 
Join Date: Jul 2005
Posts: 81
Blower Stops Momentarily '91 350 SD

With the a/c set at the coldest setting and blower speed on high, occasionally the blower will stop for a few seconds and then restart. I have been putting the fan on the low setting when this happens. I checked the strip fuse and tightened the mounting screws. Any thoughts on what might be causing this?

FWIW: With 100 degree temperatures in NJ today, I'm getting a delta t of about 30 degrees F at the middle vent with recirculation on; PO converted to 134a. With these extreme temperatures, I'm seriously thinking about going back to R12.

Greg
Reply With Quote
  #156  
Old 07-22-2011, 11:29 PM
vstech's Avatar
DD MOD, HVAC,MCP,Mac,GMAC
 
Join Date: Mar 2006
Location: Mount Holly, NC
Posts: 26,518
it stops on high? odd. bearings would be my guess... as in high, the resistor pack is out of the circuit. your fuse is the original or the upgraded strip fuse on the fender? 91 should be on the fender, and the 30 amp strip fuse may be cracked... pull it and look it over carefully.
__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!
Reply With Quote
  #157  
Old 07-23-2011, 12:00 AM
Registered User
 
Join Date: Sep 2001
Location: central Texas
Posts: 17,281
Greg... to put that Delta T into perspective.... a room AC only expects to provide 6-8 degrees difference....
It may not be providing all the cooling you want or need...but it is doing a lot of work in these record temps and high humidity....
Reply With Quote
  #158  
Old 07-23-2011, 11:28 AM
Registered User
 
Join Date: Jul 2005
Posts: 81
Thanks for the input guys.

The strip fuse is located at the firewall. The holder looks like it has been overheated a few times (partial melting of the plastic). Is there an upgrade available? In the meantime, I'll put in a new strip fuse. The one that's in there I replaced about 3 years ago and it looks a bit oxidized, but the contacts seem to be secure.
Reply With Quote
  #159  
Old 07-23-2011, 11:44 AM
Registered User
 
Join Date: Jun 2008
Location: Orlando, FL
Posts: 1,269
I recently found a tank of R12 in my grandpas garage (a TANK!) and will be putting it in my newly rebuilt AC system. My question is how do I measure the 2.6 pounds required to fill the system when using the tank? Is it as easy as putting it on a scale and watching it's weight drop or a little more difficult than that?
Reply With Quote
  #161  
Old 07-23-2011, 03:15 PM
vstech's Avatar
DD MOD, HVAC,MCP,Mac,GMAC
 
Join Date: Mar 2006
Location: Mount Holly, NC
Posts: 26,518
a UPS digital scale can do it, We professionals use refrigerant digital scales.
__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!
Reply With Quote
  #162  
Old 07-23-2011, 04:50 PM
Registered User
 
Join Date: Jul 2005
Posts: 81
W126 Blower Inop.

Quote:
Originally Posted by vstech View Post
it stops on high? odd. bearings would be my guess... as in high, the resistor pack is out of the circuit. your fuse is the original or the upgraded strip fuse on the fender? 91 should be on the fender, and the 30 amp strip fuse may be cracked... pull it and look it over carefully.
On a short trip this afternoon, the a/c was working fine; blower on max. I shut the vehicle down for a few minutes without pressing "0" to shut off the a/c. Upon restart, no blower, but the compressor clutch is engaging. I checked the strip fuse (ok) and changed #5 fuse in the box next to the brake booster as a precaution. I think I found the blower motor on the passenger side of the vehicle behind an interior trim panel and a Behr cover with an aluminum heat exchanger mounted to it. I pulled the red and blue wires off of the motor and attached a trouble light. The light illuminates with the fan controls. My next check will be to apply 12v to the motor directly. Assuming it doesn't run, how do I remove the blower motor? Can someone provide direction here? John mentioned bearings above. Are the bearings serviceable or do I just replace the motor? Vehicle is a '91 350 SD.

Thanks in advance.

Greg
Reply With Quote
  #163  
Old 07-31-2011, 11:37 AM
vstech's Avatar
DD MOD, HVAC,MCP,Mac,GMAC
 
Join Date: Mar 2006
Location: Mount Holly, NC
Posts: 26,518
I moved the conversation to it's own thread.
A/C problems, help needed.
__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!
Reply With Quote
  #164  
Old 08-07-2011, 01:00 AM
Registered User
 
Join Date: Jun 2008
Location: Orlando, FL
Posts: 1,269
Another question about filling with a tank...

Is there any special trick to it? On my tank it has an arrow pointing up that says "gas" and another pointing down that says "liquid" in terms of how you want the stuff to go in to the system. I know that with cans you are supposed to rock the can side to side to get it all in, but from what I've said not with a tank.

I'm assuming that I just let the tank sit on it's own and not touch it, the liquid will turn to gas anyway, but I wanted to double check before I accidentally waste some precious R12.
Reply With Quote
  #165  
Old 08-07-2011, 01:17 AM
Registered User
 
Join Date: Oct 2005
Posts: 4,263
Liquid in the low-side line can slug the compressor. You only charge with liquid with the compressor off. If you are charging from the low-side line with the compressor running, it's gas only.

Liquid doesn't turn to gas on its own. It takes heat.

Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 09:31 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2022, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page