Date: Tue, 19 Jul 2005 15:32:24 -0700
Reply-To: Keith Hughes <keithahughes@QWEST.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Keith Hughes <keithahughes@QWEST.NET>
Subject: Re: AC converted to 134
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>Date: Tue, 19 Jul 2005 12:55:17 -0700
>From: Keith Ovregaard <kovregaard@COMCAST.NET>
>Subject: Re: AC converted to 134
>
>Keith
>Looks like the Keith's are in agreement here. Although I am not certain=20=
>
>of a high pressure AC switch on my 84. No doubt the relays are set to=20
>give priority to the high speed fan at the expense of the AC=20
>compressor. Meant to be that way, it seems. I don't think anything=20
>abnormal is happening with the radiator: no discolored fluid, no leaks,=20=
>
>apparently good circulation, resent/frequent coolant change (VW=20
>approved) and normal operation for 10 years. Just looks to me like the=20=
>
>old 84 has trouble running the AC at temps in the triple digits. Or am=20=
>
>I still missing something?
>
>Keith O
>
Keith,
The only thing you're missing is adequate cooling :-)
The '84, as others have said, has no high pressure switch. The second
setpoint on the thermoswitch turns the fan on high, and energizes the
compressor cutout relay. The system, pre '86 is not legal to retrofit
to 134A without addition of a high pressure switch. The post '86
systems, although they have a high pressure switch, are not *legal* to
convert either, in that the high pressure switch must be configured to
disable the compressor, which the Vanagons' aren't.
I don't think you have an A/C problem at all. You have an overheating
problem. The lifter clatter, in conjunction with tripping the high temp
switch (radiator) is indicative of overheating. Oil gets too thin, and
worn lifters can't stay pumped up. In my '86, here in Phoenix, I could
not keep it running cool enough with the old WBX'er, even with a new
cooling system (and +200K on the motor). When it got into triple
digits, which can be >100 days a year, the A/C was unusable. The fan
was on high often/long enough that the A/C just didn't cool.
As for the clatter, I don't know where you live, but here, I ran
straight 50W (60W if it was going to be >115°F for some time) in the
summer, and 40w in the winter, which helped the oil pressure problem.
Use to do the same with Buses, which were even worse - 80K on a bus
motor here in Phoenix is about all you can hope for. Even so, after a
couple 100K's on the motor, it was time for a new one. Good luck,
Keith
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