AC re-charging not working - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Grand Cherokee & Commander Forums > ZJ Grand Cherokee Forum > AC re-charging not working

New DEAL OF THE WEEK at ROCKRIDGE 4WD!FS: Wrangler RGB Multicolor Fog Light LEDs: Awesome EffectFS: 2007-2013 Jeep Wrangler "HALO" Angel Eye Kit

Reply
Unread 07-01-2014, 09:54 AM   #1
moojamboo
Registered User
1994 ZJ 
 
Join Date: Jul 2013
Location: underhill, vt
Posts: 36
AC re-charging not working

So i will admit AC is not a strong point so i appologize up front if i use terms incorectly.

the AC in my 94 ZJ limited 5.2 V8 is not cold at all. so i bought one of those AC pro recharge kits with the gauge and attempted to recharge the system. i found the low side port according to documentation i found which i believe for this vehicle is on the passenger side rear corner of the engine bay.



the compressor does not run but seems to move freelly by hand. so according to the instructions i'm suposed to empty half the can of 134a into to the system then recheck the pressure. the pressure is around 700psi on the gauge in the red zone which i have read is normal if the compressor isn't running due to low volume of refrigerant.

when i squeez the trigger to release refrigerant i get a hiss and a puff of stuff comes out of the trigger is this normal? i thoght i had a defective can/trigger but as with the first can i bought i had liquid dripping down the trigger after 10min of trying to recharge the system, but the second can i bought has the same thing occuring.

what am i doing wrong? is the low side port not the one i have shown above? is there a different port i'm suposed to be putting this into? is it normal and i just am realy really low on refrigerant?

thanks for any help you have.

moojamboo is offline   Reply With Quote
Unread 07-01-2014, 10:26 AM   #2
Smokey1r
Registered User
1997 ZJ 
 
Join Date: Aug 2009
Location: Macomb, Illinois
Posts: 595
You have the correct port, but its always best if possible to vacuum down the system prior to recharging so you can draw out the moisture that is resident in the air contaminating the system, the air in it will diminish the performance of and cause corrosion in the system.

You will need about 24 ounces of freon to fill the system give or take a few ounces depending on how much oil is in the system also.

When trying to fill the system initially it will be very slow as the compressor will not kick in till there's enough freon in it to engage it safely, then it will cycle on and off every few seconds, when the compressor kicks in that's when you want to pull the trigger on the freon can with it upside down as the lower pressure created with the compressor running will allow the freon to enter with greater ease, keep doing this till you have close to the correct amount of freon in, you will notice the compressor will cycle on longer as more freon enters the system, also feel the low side line where your attached for a massive temperature drop as this will indicate the freon it entering the system.

Sometimes it takes a bit of time for it to initially enter in as the can seal sometimes is only slightly punctured coupled with the cheap trigger that leaks, so keep that trigger fully depressed when needed as what your describing is normal for that method of charging. The pressure guage isnt accurate on those things so its best to gauge it by feel when charging.

Be patient with it and you will see the compressor staying on longer and longer as the system reaches its capacity and the amount of liquid in the can decreases when you give it a slight shake to determine the level in the can.
Smokey1r is offline   Reply With Quote
Unread 07-01-2014, 10:44 AM   #3
moojamboo
Registered User
1994 ZJ 
 
Join Date: Jul 2013
Location: underhill, vt
Posts: 36
i have put in more than half the can so i would say between 10 and 15oz of the can orginally and the compressor still hasn't cycled on.
moojamboo is offline   Reply With Quote
Unread 07-01-2014, 11:49 AM   #4
monkeyhouse
Registered User
1997 ZJ 
 
Join Date: Sep 2009
Location: Cumberland, Maryland, Maryland
Posts: 3,151
Quote:
Originally Posted by moojamboo View Post
i have put in more than half the can so i would say between 10 and 15oz of the can orginally and the compressor still hasn't cycled on.
You can jump the relay for the compressor to make sure it is functional, but just to check it, don't let it run long. I'm doing the same thing you are. I still haven't seen a difference and I notice that the time the compressor stays on has yet to change. about 9-10 seconds off, 3 seconds on. I'm going to see if I can get a set of manifold gauges today from autozone so I don't over charge the system.
__________________
First Jeep was an 1989 YJ, 6 cylinder 4.2L , 258. Nuttered and TeamRushed, Weber 38 DGES, Now, I'm venturing into the world of Grand Cherokees
monkeyhouse is offline   Reply With Quote
Unread 07-01-2014, 12:54 PM   #5
Oldfrog
Web Wheeler
1997 ZJ 
 
Join Date: Feb 2008
Location: Louisiana/Texas
Posts: 3,804
Jump it and fill it a little.
Then remove the jumper, plug it back in and fill it to the right pressure.
Your r134a didnt get in. due to the leak and the compressor clutch not being engaged.
__________________
Cajun Recipes and Fishing tips

Words of wisdom, Posted by Zeejay:
"..it's not air, it is the opposite of air... suckage so to speak."

Stalling? Work through Zeejay's list
Oldfrog is offline   Reply With Quote
Unread 07-01-2014, 01:24 PM   #6
monkeyhouse
Registered User
1997 ZJ 
 
Join Date: Sep 2009
Location: Cumberland, Maryland, Maryland
Posts: 3,151
Quote:
Originally Posted by Oldfrog View Post
Jump it and fill it a little.
Then remove the jumper, plug it back in and fill it to the right pressure.
Your r134a didnt get in. due to the leak and the compressor clutch not being engaged.
Yeah, I really missed that when researching yesterday and I was filling it mostly when it wasn't spinning. I am still getting the gauges though because that can gauge read zero before I started and once I got some in, it was fluctuating between 25(not spinning) and 65 (spinning). Thanks
__________________
First Jeep was an 1989 YJ, 6 cylinder 4.2L , 258. Nuttered and TeamRushed, Weber 38 DGES, Now, I'm venturing into the world of Grand Cherokees
monkeyhouse is offline   Reply With Quote
Unread 07-01-2014, 01:28 PM   #7
monkeyhouse
Registered User
1997 ZJ 
 
Join Date: Sep 2009
Location: Cumberland, Maryland, Maryland
Posts: 3,151
Quote:
Originally Posted by moojamboo View Post
i have put in more than half the can so i would say between 10 and 15oz of the can orginally and the compressor still hasn't cycled on.
You'll have to force it to run:
compressorcluctchjump.jpg  
__________________
First Jeep was an 1989 YJ, 6 cylinder 4.2L , 258. Nuttered and TeamRushed, Weber 38 DGES, Now, I'm venturing into the world of Grand Cherokees
monkeyhouse is offline   Reply With Quote
Unread 07-01-2014, 10:57 PM   #8
Dukcaln
Registered User
 
Join Date: Sep 2013
Location: Vacaville, California
Posts: 469
good info here guys, when I got my zj last year it was not blowing cold and the compressor didnt cycle on, I jumped it, got a few oz from the can in it and bam, she filled right up and worked perfect, still very cold!

moojamboo, how is it going, any update?
__________________
1996 zj-v8-79k miles-corbeau seats-exhaust-hood vents-3 1/2 lift-safari rack-arb bumper-amps-subs
Dukcaln is offline   Reply With Quote
Unread 07-02-2014, 07:27 AM   #9
monkeyhouse
Registered User
1997 ZJ 
 
Join Date: Sep 2009
Location: Cumberland, Maryland, Maryland
Posts: 3,151
Quote:
Originally Posted by moojamboo View Post
i have put in more than half the can so i would say between 10 and 15oz of the can originally and the compressor still hasn't cycled on.
Did you have any luck? I jumped mine yesterday and used a can of AC Pro. It took me almost the whole 20 oz, but it has been fine for the past 24 hours. ....and it's supposed to be hot today!
__________________
First Jeep was an 1989 YJ, 6 cylinder 4.2L , 258. Nuttered and TeamRushed, Weber 38 DGES, Now, I'm venturing into the world of Grand Cherokees
monkeyhouse is offline   Reply With Quote
Unread 07-02-2014, 07:38 AM   #10
elijahpr
Registered User
1998 ZJ 
 
Join Date: Mar 2014
Location: Portland, ME
Posts: 293
Defiintely try jumping it... just did this two days ago, my compressor wouldn't even kick on at all. Now it works perfectly, except I think I need a little more freon to add.
__________________
1998 Grand Cherokee TSi
3-inch Rough Country Lift
elijahpr is offline   Reply With Quote
Unread 07-02-2014, 08:41 AM   #11
Uniblurb
Web Wheeler
 
Uniblurb's Avatar
1996 ZJ 
 
Join Date: Jan 2012
Location: Central, Ohio
Posts: 3,381
Just a good AC recharging tip I learned on here. If you want the 134a to go into the system a whole lot faster put the can in a container of real hot water. I used a couple of those plastic 3lb coffee cans full of hot water and it causes the 134a to vaporize/enter the low pressure port as a gas which is better for the system than turning the can upside down entering as a liquid. Couldn't believe how much this sped up the recharging process as the clutch was kicking on but you still have to watch your gauge(s) closely.

I used to borrow the sets of AC manifold gauges from Advance and/or Autozone but ended up buying my own. Most don't realize Autozone also has loaner AC vacuum pumps which have come in real handy. But these are for an empty AC system and not for 134a recovery. I pulled the vacuum down, let it set overnight although they say 1-2 hours may be sufficient, and vacuum held so knew I didn't have any leaks.

Real good $68 investment for a good AC manifold gauge set since I maintain the AC systems on multiple Jeeps. They also sell less expensive ones which may work and helps to read the reviews. You also need about a $12 valve for going from the small 134a cans to the gauge set suction line.

http://www.amazon.com/Actron-CP7806-...c+gauges+r134a

If using a manifold gauge set this chart from the 96 FSM may help on the correct charge according to ambient temps around the engine bay. Often they'll have a chart on the large 134a cans, or in the directions, but this one's more specific to the ZJ's.
ac-performance-temp-pressure-chart-p.24-10.jpg

__________________
96 4.0 ZJ Laredo, 2004 4.7L WJ Limited, 93 4.0 XJ (spare), 96 4.0 XJ (son's)

-Stalling ZJ? 12 things to check before replacing a sensor; the Dirty Dozen
-Crankshaft position sensor multimeter test. & video of testing.
Uniblurb is offline   Reply With Quote
Unread 07-02-2014, 02:54 PM   #12
zj97ltd
Registered User
1993 ZJ 
 
Join Date: Apr 2013
Location: Cape Coral, FLORIDA
Posts: 1,067
Keep in mind too that a/c is a sealed system. If the refrigerant is low, it's because it leaked out somewhere. Just adding refrigerant without correcting the leak is just a temporary fix.
zj97ltd is offline   Reply With Quote
Unread 07-03-2014, 10:01 AM   #13
moojamboo
Registered User
1994 ZJ 
 
Join Date: Jul 2013
Location: underhill, vt
Posts: 36
Update!...found out it was the clutch cycling or low pressure switch as soon as it was jumped the compressor ran...of course i then had too much refrigerant in the system because that wasn't the original issue. so i had to have that taken out. now everything works great...by the way the switch has been discontinued by Jeep so i had to find a third party switch. took some looking but finaly found one at autozone for around $16 in case anyone else has an issue.

thanks for all the help.
moojamboo is offline   Reply With Quote
Unread 07-03-2014, 10:08 AM   #14
Uniblurb
Web Wheeler
 
Uniblurb's Avatar
1996 ZJ 
 
Join Date: Jan 2012
Location: Central, Ohio
Posts: 3,381
Real cheap fix and glad you figured it out!
__________________
96 4.0 ZJ Laredo, 2004 4.7L WJ Limited, 93 4.0 XJ (spare), 96 4.0 XJ (son's)

-Stalling ZJ? 12 things to check before replacing a sensor; the Dirty Dozen
-Crankshaft position sensor multimeter test. & video of testing.
Uniblurb is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.