Gary,
Not sure about your first question.
As to the second, my '90 Westy was converted some years ago and after  the first year
or so, I had to start adding a can or more (I live in a hotter climate than you do)
every season.
I mostly went by how cold the air was or was not, and it usually took 3/4 to a full
can to bring it back down. My own feeling is that with the small cans, it is pretty
hard to overfill.
If you haven't done it before, be aware that the bottom of the can will get icy cold
and it will move up as the can empties, so wear gloves or hold the can by the top. It
also helps speed the charge if you put the can in a pan of hot (not too hot) water
while charging.
A few weeks ago, I added a two-part leak sealer made by Interdynamics that I found at
WalMart. The good news for me is that the system still works (always suspicious of
miracle cures), but I need to give it some more time to see if it worked. It is
supposed to seal leaks in both rubber parts and metal parts.
Jerry
----- Original Message -----
From: "gary hradek" <hradek@YAHOO.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Saturday, May 11, 2002 3:56 PM
Subject: emergency radiator fan manual switch and other

> For those who have ac, Can anyone see why there would
> be a problem with pulling the electrical connection to
> the ac compressor at the pump and using the ac switch
> to turn the radiator fan on and off when there is a
> problem with the temp sensor on the radiator.   Are
> there any other times when this backup could be used?
> Will this actual work?
>    I have converted to r134.   Is there any problem
> adding a can a year to the system to off set any loss
> since the hoses are the wrong kind for r134?   I do
> not have a gauge to measure pressure.   What are the
> symptoms when the high pressure side goes too high?
>                    thanks, gary
>
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