If the system was bled properly and the actual operating temperature (as
measured at the engine by a reliable instrument) is in spec, the next step
is to check it for HC in the cooling system. Requires a chemical test
(tester available from NAPA or other FLAPS) or an exhaust gas sniffer - any
HC in cooling system means leaky head gaskets or cracked heads.

I presume you mean out of the overflow reservoir behind the license plate
when you say "from under the coolant expansion tank cap"? You say you
replaced the tanks and caps - does that mean with new parts, or used? The
cap IS supposed to open and close to allow small amounts of coolant to
transfer back and forth between the overflow and main tanks, but if the
stuff is overflowing the overflow, that's going too far. Could be a bad cap,
although that would be unusual, if it's a new one. I once had a reservoir
tank chronically leaking into the overflow - turned out the plastic was
eaten away at the surface that seals the bypass seal against the tank.

Coby Smolens
Valley Wagonworks
VW Bus and Vanagon Specialists
"Intimately acquainted with VW Vans since 1959"

1535 SF Drake Blvd, San Anselmo, CA 94960
415-457-5628

 -----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM]On Behalf Of
jeff emrick
Sent: Friday, August 24, 2001 2:56 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Coolant leaking

  After driving my 84 Vanagon I notice coolant coming from under the coolant
expansion tank cap.  I'm not sure if the van is running hot or not.  The
water temp gauge doesn't work well all the time.  The cap is on tight.  I
just replaced the coolant and refill tanks and caps, new thermostat,
coolant,  and bleed the whole system.  Is the cap supposed to open and close
to allow for a pressure release?  Could I just have a bad cap?  Any thoughts
would be appreciated.  Thanks, Jeff

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