You either have a pressure cap that is not holding or you are in fact
getting combustion gasses into the cooling system. Latent air in the
system will work its way out but if you are pushing out enough coolant to
force excess out of the over flow, then you are filling it with something
extra.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Richard Golen
Sent: Friday, December 28, 2007 8:21 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Air in cooling system....or is this normal

Hi,

We just drove up to Fairport, NY to visit my 8 month old grandson
(and of course his parents), a distance of 415 miles. We stopped for
the usual "pit stop"about 150 miles out, and I noticed that the
overflow coolant tank was almost full to the top and coolant was
dripping out and leaving a puddle beneath our 87 Westy. I bled out
some of the coolant, and drove out while keeping a watchful eye on
the coolant gauge. The gauge stayed in the center for the next 250
miles, with a little movement upward while going up hill, and
dropping a bit below center while going down hill. We stopped about
300 miles out, and the coolant was just up to the cap on the overflow
tank.

Now that we've been at the hotel for 90 minutes, I checked the
coolant level and it was now back to normal between the min and max
lines. Now, I've owned the 87 for 8 years now and never noticed the
overflow tank so full or spitting out coolant, so I'm a bit puzzled.
Another interesting behavior was that the heater would run cool and then
hot.

Could there have been some latent air somewhere in the coolant lines
that finally may have expanded and caused the coolant level to go
nuts and to cause the hot/cold heater??

Ric