Throw me a bone:93 ZJ ac issue
#1
Seasoned Member
Thread Starter
Join Date: Apr 2011
Location: Outside of RTP NC
Posts: 451
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1993
Model: Grand Cherokee
Engine: V8
Throw me a bone:93 ZJ ac issue
93 ZJ
New Expansion Valve (line), New accumulator, New compressor, New Evap, New clutch cycling switch. Pressures are rock steady, NO needle movement unless the clutch cycles (which is not alot) . 95 degrees plus ambient temp. 240 high and 44 low. Started out over charged and we pulled freon out to achieve those numbers. Was over 70 and over 275.
Blows very cool, with plenty of air flow but never gets cold. Heater core is 100% bypassed for the time being, NO coolant flow what so ever.
Why the devil is it not COLD?
Thanks
Ron
New Expansion Valve (line), New accumulator, New compressor, New Evap, New clutch cycling switch. Pressures are rock steady, NO needle movement unless the clutch cycles (which is not alot) . 95 degrees plus ambient temp. 240 high and 44 low. Started out over charged and we pulled freon out to achieve those numbers. Was over 70 and over 275.
Blows very cool, with plenty of air flow but never gets cold. Heater core is 100% bypassed for the time being, NO coolant flow what so ever.
Why the devil is it not COLD?
Thanks
Ron
#2
CF Veteran
Join Date: Feb 2010
Location: Oroville, CA
Posts: 12,367
Likes: 0
Received 19 Likes
on
18 Posts
Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
I honestly think it's a crap design in the early ZJ. What is your air duct temp at the center duct with the fan on medium? The best I ever got out of my 95 ZJ was 42 degrees.
#3
Seasoned Member
Thread Starter
Join Date: Apr 2011
Location: Outside of RTP NC
Posts: 451
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1993
Model: Grand Cherokee
Engine: V8
No where near 42 degrees. I did not have a thermometer handy at the time, but best guess is somewhere around 60 degrees. Cool, for a 95 degree day, but darn sure not cold.
What Im baffled about is the pressure split, it could not be closer to perfect, yet I got squat.
Someone suggested I pull the system back down and only put back in the 28 oz it calls for. With that said, the pressures are right!
Thanks
Ron
What Im baffled about is the pressure split, it could not be closer to perfect, yet I got squat.
Someone suggested I pull the system back down and only put back in the 28 oz it calls for. With that said, the pressures are right!
Thanks
Ron
#4
CF Veteran
Join Date: Feb 2010
Location: Oroville, CA
Posts: 12,367
Likes: 0
Received 19 Likes
on
18 Posts
Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
I'm going through the same thing with mine. I just replaced the evaporator and liquid line, pulled a vacuum for a long time and charged the system. Good pressures, but not real cold.
#5
Old fart with a wrench
Which refridgerant are you using? I know systems that were designed to run on R12 don't cool as well with R134. My older Chevys would freeze your chest hair, but my 89 truck converted to R134 was disappointing.
#6
Seasoned Member
Thread Starter
Join Date: Apr 2011
Location: Outside of RTP NC
Posts: 451
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1993
Model: Grand Cherokee
Engine: V8
134a
Just for argument, we pulled it back down and charged the 28 oz it call for.
Pressures suuucked, but its ice cold. After 30 mins at highway speed its below 40 degrees. At idle in the shop we were over 60 psi on the low and about 280 on the high side. Neither of these numbers are what I would call ideal but its cooling fine, and based on at least one source the numbers are in the "normal" "range"
Ron
Just for argument, we pulled it back down and charged the 28 oz it call for.
Pressures suuucked, but its ice cold. After 30 mins at highway speed its below 40 degrees. At idle in the shop we were over 60 psi on the low and about 280 on the high side. Neither of these numbers are what I would call ideal but its cooling fine, and based on at least one source the numbers are in the "normal" "range"
Ron
#7
CF Veteran
Join Date: Feb 2010
Location: Oroville, CA
Posts: 12,367
Likes: 0
Received 19 Likes
on
18 Posts
Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
I miss R12, it worked so much better than R134a. It won't be long before 134 is phased out and we have to retrofit for the new stuff.
Trending Topics
#8
Old fart with a wrench
Of course the best stuff is ammonia, but only large industrial freezers can use that.
Just thought I'd throw that out there and see if it comes back. LOL!
Just thought I'd throw that out there and see if it comes back. LOL!
#10
Seasoned Member
Thread Starter
Join Date: Apr 2011
Location: Outside of RTP NC
Posts: 451
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1993
Model: Grand Cherokee
Engine: V8
Mom had a Chevy Blazer, the little one, the first year 134 was introduced. The condenser on that truck was thicker than the radiator. Lived on the NC/SC state line, where the temp hovered in the 90's with 85% to 90% humidity. That truck would put frost on your pumpkins in less than 20 mins! POURED condensate like a faucet.
134 is LESS efficient, however if you offset the efficiency with a little better hardware it works damn nice!
Ron
134 is LESS efficient, however if you offset the efficiency with a little better hardware it works damn nice!
Ron
Thread
Thread Starter
Forum
Replies
Last Post
carverdave
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
7
02-06-2019 08:55 AM
shelby5041
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
39
11-07-2015 01:22 AM
Azzy
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
0
09-08-2015 10:49 PM
TNXJsleeper
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
1
09-02-2015 05:31 AM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)