Date: Mon, 20 Jun 2016 00:14:33 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: AC INOP 1988 GL WBX 2.1
In-Reply-To: <CA+az7_5Oj25cQQ0Kcv6Ud+B7dnpzCCejAD2f78VCxwQckhG_Hg@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"
I know this is a little bit tough to hear but if you really need to ask how to troubleshoot the AC compressor clutch you should not be doing this work. While R-134a is available un-licensed in the under 1 pound containers it is a controlled refrigerant. That said it is extremely rare for the AC clutch itself to fail. As for it being "operated" there are a number of requirements for it be turned on. That includes the system being at a minimum pressure and under a maximum pressure and the thermostat needs to call for AC. There is also usually a low temp cut off (must be above freezing). Then after all the conditions are meet you need to look for electrical failures. The AC in these vans is known for many wires, fuse blocks, and relays to fail. Sometimes in quit spectacular (burned out stuff), ways. Remove the cover on the driver's side pillar and you will see a lot of electrical stuff there.
AC systems are amazing in their ability to take on moisture, even with some pressure inside. If you lost enough refrigerant to take a charge without the compressor running you probably also have stuff inside that does not belong. As such even if you get to work somewhat the contamination will create internal corrosion that later on will make a real mess. Moisture inside can also create ice crystals which can make a real mess at the expansion valve. Freeze and block the expansion valve and you can create excessive head pressure and even lock up the compressor. If the belt or clutch doesn’t slip than broken parts are the next step.
Educate the right way and unless you are willing to get the tools leave the AC to someone that knows (hopefully) what they are doing.
Dennis,
With 297,500 miles on Fun Bus with both the original engine and AC compressor and the AC is still working even with R134a.
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of John Rodgers
Sent: Sunday, June 19, 2016 8:52 PM
To: vanagon@GERRY.VANAGON.COM
Subject: AC INOP 1988 GL WBX 2.1
Went to recharge the AC today. Everything went well until ---
I got one can of refrigerant into the system, cranked the engine and found the clutch will not engage, nor will it take any more refrigerant with engine running or not. Refrigerant lines felt cool as the first can went in but not since. The AC controls were set properly, but no go. How does one go about checking the clutch while the compressor is on the engine? I can hear a faint clicking like something turning on and off, but not sure what it is. The system still had some 135a in it but it got low enough to shut itself off last year. Haven't run it since.
This is my first foray into the vanagon AC. Lots of mysteries to learn about. Any suggestions?
John
