Be sure your coolant lines to the radiator were crossed over for proper flow
through the radiator per the Bostig installation manual:
https://bostig.zendesk.com/entries/25075132-Bostig-Factory-Manual .  A good
Vanagon radiator has plenty of capacity, so I think you may have a plumbing
issue.  Email the folks at Bostig as well.
https://bostig.zendesk.com/anonymous_requests/new

I remember a couple of years ago when I was considering the Bostig
conversion they were recommending pinching one of the coolant lines because
the radiator was too effective.  I think it was just a hose clamp with a
block of wood or some such thing.  Check for that up over the spare tire.

Good luck!

Stuart

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Geneva Saint-Amour
Sent: Tuesday, July 08, 2014 4:53 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Cool it...

The gauge got to the top.  The red light blinked.  We pulled over.  The fan
came on.  Just one speed.  The radiator is 3 years old.  The air is purged.
We have a dash switch for the fan.Keep it coming.... I am a sponge, soaking
up your information and ideas.

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