I tested my new cap by blowing into it.  It made a sound like a kazoo!  Should be able to blow through it with minimal resistance, since these have a spring loaded rubber flap sealing gasket.  Rinse off all the coolant and try it.  I got mine from Van Café, and it's made by Blau, their preferred brand.  Has a triangle on the top.

Stuart

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Dan N
Sent: Saturday, October 17, 2015 11:44 AM
To: vanagon@GERRY.VANAGON.COM
Subject: coolant in expansion reservoir

hi,

I flushed and replaced the coolant in my 1990 Carat..

all went well, properly bleed, new blue pressure cap etc... but I need to add coolant to the main reservoir (w. blue cap) after 20 or so miles...

I noticed that the coolant from the expansion reservoir doesn't go to the main reservoir... it stays full while the level of the coolant in the main reservoir went down... then I let it sit overnight... same thing happened...

is this normal or something wrong? not enough vacuum to suck the coolant back to the main reservoir?

thanks in advance

dan