NAPA has a UV test kit for $30 I'm going to invest in.  Parts are too expensive to throw at a problem like this. 

I'm also worried about my '85.  I did have the overflow tank spew coolant after a 20 mile drive on my last trip.  No bubble in the expansion tank, so I just sucked a bit out and it's been fine now for about 50 miles.  Maybe it won't happen again.  I did have a leak just before this and took out the two rusted tees to the rear heater.  Hopefully there was just a bubble in there somewhere.

Stuart

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Neil N
Sent: Monday, September 28, 2015 2:28 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Missing coolant

Also, coolant can leak out between coolant level sensor and tank, pool at that point and evaporate.

On Mon, Sep 28, 2015 at 2:21 PM, Jim Felder <jim.felder@gmail.com> wrote:

... Ive had it spray onto the
> engine in such small quantities that it would evaporate before you 
> could see it.

--
Neil n

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