TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > Body/Interior > HVAC
  New Posts New Posts RSS Feed - Replacing A/C Expansion Valve
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

Replacing A/C Expansion Valve

 Post Reply Post Reply Page  12>
Author
Message Reverse Sort Order
White70JavelinSST View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar

Joined: Aug/08/2012
Location: Minnesota
Status: Offline
Points: 4867
Post Options Post Options   Thanks (0) Thanks(0)   Quote White70JavelinSST Quote  Post ReplyReply Direct Link To This Post Topic: Replacing A/C Expansion Valve
    Posted: Aug/09/2017 at 4:47pm
Remember when using two wrenches in unison like that, one to hold the body and one to move the nut, the closer the two wrenches are to each other when trying to loosen the nut the better control and more power you will have. If the two are spread apart too far it puts your hands at a disadvantage.
70 Javelin SST, second owner, purchased 1972
Back to Top
amcenthusiast View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jul/02/2012
Location: SW Atlanta GA
Status: Offline
Points: 1778
Post Options Post Options   Thanks (0) Thanks(0)   Quote amcenthusiast Quote  Post ReplyReply Direct Link To This Post Posted: Aug/08/2017 at 10:54pm
Last expansion valve I did was on a '65 Marlin by buying a big expensive open and closed end wrench to fit on the evaporator core side and customized it so I could put an extension on it for more leverage= I was able to get enough leverage to pop it loose/worked for me.

I'm pretty sure that when R134a is mixed with the old refrigerant the combination forms crystalized abrasives in the system; this may the cause of your compressor seal failures... (some refrigerant leaks past the compressor pistons and gets into crankcase oil) -the entire system needs to be flushed/rinsed out with mineral spirits, blown out with compressed air, including the compressor crankcase to get rid of any trace of the older refrigerant and oils when putting new 134a into an older system.


443 XRV8 Gremlin YouTube video: https://www.youtube.com/watch?reload=9&v=2DmFOKRuzUc
XRV8 Race Parts website: http://amcramblermarlin.1colony.com/
Back to Top
EdwardSharp View Drop Down
AMC Fan
AMC Fan


Joined: Aug/08/2017
Location: Tigard
Status: Offline
Points: 1
Post Options Post Options   Thanks (0) Thanks(0)   Quote EdwardSharp Quote  Post ReplyReply Direct Link To This Post Posted: Aug/08/2017 at 7:16am
For replacing A/C expansion valve or any other problems related air conditioners I would suggest to contact local air conditioning service essex county nj experts, who has relevant amount to experience and knowledge to solve your problem effectively. Get more info at :
https://essexheatingcooling.com





Back to Top
401MATCOUPE View Drop Down
AMC Addicted
AMC Addicted


Joined: May/20/2010
Location: Salisbury, MD
Status: Offline
Points: 5370
Post Options Post Options   Thanks (0) Thanks(0)   Quote 401MATCOUPE Quote  Post ReplyReply Direct Link To This Post Posted: May/04/2017 at 9:04am
Steve,

They have these great electronic sniffers now that can find leaks down to 1/10 ounce per year.....they work great.  This is a new version of what I have.

http://www.mastercool.com/product/55200/

Ross
Ross K. Peterson
68X,GoPac,343,AT,52A(1stCar)
68X,GoPac,390,4sp,52A
69X,GoPac,390,4sp,64A
70X,GoPac,390,4sp,87A,8
70X,GoPac,390,4sp,BBO,8
70 Jav SST,390,AT,BSO
74MatX,401,AT,Prototype
74MatX,401,AT
Back to Top
S Curry View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Aug/16/2012
Location: Iowa
Status: Offline
Points: 598
Post Options Post Options   Thanks (0) Thanks(0)   Quote S Curry Quote  Post ReplyReply Direct Link To This Post Posted: May/04/2017 at 7:42am
Ross. Thanks for that info. Maybe that is why you don't see them anymore. I'm sure there are better devices for finding leaks. That is what we used. It was a hose attached to the lower side of the bonnet on a hand held propane torch. It would turn colors when finding a leak. Not very handy while under the dash. Would vac 'em down for a half hour, charge them up, do a quick checks for leaks and check high and low side pressure and out the door.....time was money!!
SC
Back to Top
6768rogues View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jul/03/2007
Location: United States
Status: Offline
Points: 6234
Post Options Post Options   Thanks (0) Thanks(0)   Quote 6768rogues Quote  Post ReplyReply Direct Link To This Post Posted: May/04/2017 at 7:34am
If you replaced the dryer, a short time under vacuum will do. If not, I leave 27 inches of vacuum on for 8 hours or so. That will test the system for leaks and boil out any moisture in the system. Water boils at about 70 degrees under 27 inches of vacuum, so it is a good way to dry things out if they are being reused.
Content intended for mature audiences. If you experience nausea or diarrhea, stop reading and seek medical attention.

Located usually near Rochester, NY and sometimes central FL.
Back to Top
CamJam View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: Jan/04/2014
Location: Arizona
Status: Offline
Points: 6479
Post Options Post Options   Thanks (0) Thanks(0)   Quote CamJam Quote  Post ReplyReply Direct Link To This Post Posted: May/03/2017 at 4:08pm
Thanks for the helpful advice, everyone!
Back to Top
401MATCOUPE View Drop Down
AMC Addicted
AMC Addicted


Joined: May/20/2010
Location: Salisbury, MD
Status: Offline
Points: 5370
Post Options Post Options   Thanks (0) Thanks(0)   Quote 401MATCOUPE Quote  Post ReplyReply Direct Link To This Post Posted: May/02/2017 at 11:40am
Originally posted by S Curry S Curry wrote:

I would vac down for 30 min. and charge up and run a leak test. Propane torch with a hose on it...........

Steve/All,

I am not sure the R-134a and torch will work like it did with R-12.....BUT it was a terrible idea, the combustion by products are PHOSGENE GAS....aka Mustard Gas.....extremely toxic.  Phosgene Gas killed more people in WW1 then any other agent.

Phosgene is also known as carbonyl chloride (COCL2). It is formed when chlorinated hydrocarbon compounds are exposed to high temperatures.

This is from an HVAC site.......

When a refrigerant is decomposed or burned, the primary products formed are acids: Hydrochloric acid (HCI), if the refrigerant contains chlorine, and hydrofluoric acid (HF), if it contains fluorine. These products are certainly formed when hydrogen is present, such as from the breakdown of oil, water or if the refrigerant has hydrogen attached (like R-22 or R-134a). If oxygen also is present (from air or water), then it's possible to form carbon monoxide, carbon dioxide and various unsaturated carbonyl compounds -- the most notorious of which is phosgene.

Being extremely toxic in small amounts, phosgene formation was a real concern when traditional refrigerants (R11, R- 12, R- 113, R- 114) decomposed. Phosgene contains two chlorine atoms and an oxygen atom. It will only form when oxygen is present and only the refrigerants with chlorine attached will produce phosgene (not HFCs). R22 has only one chlorine atom per molecule, so it is extremely difficult, chemically speaking, to get another one attached to form phosgene. Decomposition of R-22 or HFCs may form other carbonyl fluorides, however they are not as toxic as phosgene.

Lets becareful out there!

Ross
Ross K. Peterson
68X,GoPac,343,AT,52A(1stCar)
68X,GoPac,390,4sp,52A
69X,GoPac,390,4sp,64A
70X,GoPac,390,4sp,87A,8
70X,GoPac,390,4sp,BBO,8
70 Jav SST,390,AT,BSO
74MatX,401,AT,Prototype
74MatX,401,AT
Back to Top
S Curry View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Aug/16/2012
Location: Iowa
Status: Offline
Points: 598
Post Options Post Options   Thanks (0) Thanks(0)   Quote S Curry Quote  Post ReplyReply Direct Link To This Post Posted: May/02/2017 at 11:05am
Forty two years ago this month, I started working at a AMC dealer. Folks were just starting to use AC and finding out that it wouldn't cool. I bet that month of May I changed out seals on 20 vehicles. Seal would dry up over the winter month and would fail when needed. Yes, I had to do a few twice. Keep everything extremely clean while assembling. Lint free rags are a must, too. I would vac down for 30 min. and charge up and run a leak test. Propane torch with a hose on it...........
SC
Back to Top
401MATCOUPE View Drop Down
AMC Addicted
AMC Addicted


Joined: May/20/2010
Location: Salisbury, MD
Status: Offline
Points: 5370
Post Options Post Options   Thanks (0) Thanks(0)   Quote 401MATCOUPE Quote  Post ReplyReply Direct Link To This Post Posted: May/02/2017 at 9:44am
Cameron...I NEVER put together any AMC system without replacing the Expansion Valve...but that is water under the bridge....the expansion valve would have no effect on the Compressor Seal.  I have had poor luck myself in successfully replacing the front seal, seems simple enough, but 3 out of 3 replacements blew the front seal again and I just replaced the compressor......that was with R-12, so not near as bad a hit with R-134a.  

Just make sure you if you lost system oil when the seal blew, put oil back in the system.

The best way to change the expansion valve is to remove the throttle pedal and drivers seat...that gives you enough room to use the TWO wrenches you need to break the lines loose.  DO NOT attempt to undo the nut on the hose, without backing up the tube from evaporator.......you may need to borrow a friends set of angle wrenches.

Hope this helps.....
Ross K. Peterson
68X,GoPac,343,AT,52A(1stCar)
68X,GoPac,390,4sp,52A
69X,GoPac,390,4sp,64A
70X,GoPac,390,4sp,87A,8
70X,GoPac,390,4sp,BBO,8
70 Jav SST,390,AT,BSO
74MatX,401,AT,Prototype
74MatX,401,AT
Back to Top
 Post Reply Post Reply Page  12>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.141 seconds.
All content of this site Copyright © 2018 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or