A/C system driving me crazy - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> General Rodding Tech
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 11-12-2012, 07:46 PM
Grogetter's Avatar
Registered User
 
Join Date: Mar 2005
Location: Georgetown, TX
Age: 63
Posts: 61
Wiki Edits: 0

Thanks: 1
Thanked 0 Times in 0 Posts
A/C system driving me crazy


The 1990 camaro with 3.1 that I've been working on for a while needed a new compressor (old one leaked at the clutch seal and sounded like a rock crusher)
I went to O'reilley and got a reman compressor, receiver, orifice, PAG oil, flush and refrigerant.
I removed the compressor, orifice and receiver and flushed the system components, evap, cond and all lines with the flush and then blew them out with compressed air until no liquid was coming out. BTW the old orifice had some metal and garbage in the strainer.
Then, per the instructions, I added a few oz of oil to the compressor, turned it by hand and let it sit with the clutch down for a few minutes.Then I poured the remainder of the oil into the suction hose, vacuumed the system for 1.5 hours, then recharged the system.
Again, sounds of a rock crusher and no cooling. I kept adding R134 until the clutch stopped cycling at idle. I had a fan blowing on the condenser. Still, no cooling. After a while I gave up and wrote it up to a bad remanufactured unit.

I got a second compressor, receiver and orifice and all the trimmings. Went through the same process of cleaning, but this time I added all of the oil that would go in the compressor then added the rest to the receiver. BTW, I rotated the compressor by hand to pump all of the excess oil out of the compressor both times. Evacuated the system, charged it and got the same result.
Then, I opened the system and got all of the oil out of the condenser that I could, thinking that the high side was flooded with oil that couldn't get through the orifice. Then I recharged the system and tried again.
Once I got the system closed, compressor running, small fan on the condenser I was seeing the about 30 psi on the suction side and 200 to 250 on the high side. The compressor sounds like hell when it's been off for a while then comes back on. Then quiets down a little bit as it runs but still noisier than it should be and no cooling to boot.
Can anyone give me some advice before I start throwing things??
Please!!!

Thanks

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 11-12-2012, 08:02 PM
LATECH's Avatar
Hotrodders.com Moderator
 

Last journal entry: Motor - vator
Last photo:
Join Date: Jul 2010
Location: Northeast Pennsylvania
Posts: 5,426
Wiki Edits: 0

Thanks: 230
Thanked 292 Times in 271 Posts
How much oil are we talking? Sounds like way too much oil to start with.
Also...is the condenser a serpentine or a tube type?
__________________
Fact is stranger than Fiction
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 11-13-2012, 08:44 AM
boothboy's Avatar
More bucks, go faster!
 
Last photo:
Join Date: Nov 2011
Location: Grass Valley, CA.
Posts: 621
Wiki Edits: 0

Thanks: 265
Thanked 327 Times in 290 Posts
How much refrigerant did you add? The proper amount should be on a sticker probably on the evap case. With refrigerant more is not better.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 11-13-2012, 08:25 PM
Grogetter's Avatar
Registered User
 
Join Date: Mar 2005
Location: Georgetown, TX
Age: 63
Posts: 61
Wiki Edits: 0

Thanks: 1
Thanked 0 Times in 0 Posts
I've added 8 oz of PAG oil each time based on adding up what the service manual says to add for individual component replacement. That total is 9.5 oz. However, further reading indicated that the total system capacity is 6 oz if the system is completely flushed. Bear in mind that the service manual was written with R12 in mind but I would think the oil amount would be the same. It also calls for 3.5 lbs of R-12. I wouldn't think it would take that much R-134 but that's just a WAG.

As for how much refrigerant I added, I don't know as I was feeding in vapor from a large tank and don't have a scale to use.

The condenser is two parallel passes. One manifold for all of the vapor in and another manifold for all of the liquid out, both on the same end of the condenser with u bends on the other end. The liquid outlet is at the bottom of the liquid manifold so it doesn't seem that any oil would be trapped in the condenser after flush and blow out.

I've serviced auto a/c systems for a long time as a shade tree mechanic. Used to be an appliance tech servicing window units and refrigerators so I'm not without training but I must say this is eating my lunch.

Thanks for any and all help.

Grogetter

Last edited by Grogetter; 11-13-2012 at 08:35 PM.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 11-14-2012, 08:39 AM
boothboy's Avatar
More bucks, go faster!
 
Last photo:
Join Date: Nov 2011
Location: Grass Valley, CA.
Posts: 621
Wiki Edits: 0

Thanks: 265
Thanked 327 Times in 290 Posts
Well a overcharge of either refrigerant or oir can cause the condition you describe. Too much of either can cause compressor hammering.
Reply With Quote Quick reply to this message
The Following User Says Thank You to boothboy For This Useful Post:
Grogetter (11-14-2012)
  #6 (permalink)  
Old 11-14-2012, 12:14 PM
Grogetter's Avatar
Registered User
 
Join Date: Mar 2005
Location: Georgetown, TX
Age: 63
Posts: 61
Wiki Edits: 0

Thanks: 1
Thanked 0 Times in 0 Posts
OK. I'll stop by O'Reilley this afternoon, pick up some fresh oil, evac and flush the system again, start over with 6 oz of oil, all of it in the receiver (the compressor should be well lubricated) and try it again.
Any other words of advice would be welcomed.
Reply With Quote Quick reply to this message

Recent General Rodding Tech posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
crazy hot rod driving dinger Hotrodders' Lounge 12 09-25-2010 10:27 PM
Vacuum leak is driving me crazy!!!!!! cutthroatkid Hotrodding Basics 15 06-22-2010 03:05 PM
Starter Is Driving Me Crazy.....Help Huskerboy2 Engine 3 06-16-2008 09:04 AM
Door alignment driving me crazy americanLT1 Body - Exterior 7 08-14-2007 04:06 PM
driving me crazy!!! CurtisL Transmission - Rearend 12 03-23-2004 08:49 AM


All times are GMT -6. The time now is 09:47 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.