Date:         Wed, 2 Jun 1999 02:03:13 -0700
Reply-To:     Coby Smolens <cobys@WELL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Coby Smolens <cobys@WELL.COM>
Subject:      Re: Running hot
In-Reply-To:  <3754525A.AF0C3E4A@cobaltgroup.com>
Content-Type: text/plain; charset="iso-8859-1"

> Hello,
>
> I've bled the system in my '85 Vanagon GL a couple times and it's
> still running kind of hot. The gauge stays around the white zone when
> cruising in town, but when I hit the highway (50-60 mph) it always
> stays around a bit above the red light in the middle. Is this too hot?

> After driving on the highway, if I open the engine compartment, the
> coolant reservoir is about half full of air. I open the top to let the
> air out without letter any water escape. Does this help getting air
> out of the system and if I keep doing this will it correct itself?

Sounds very like Vanagon head disease. Always, in our shop, the very first
thing in cases like this: Check for HC in the coolant. An exhaust gas
sniffer into the overflow reservoir usually does the trick if the thing
hasn't been opened since the last hard drive, otherwise you might need to
suck out some coolant from the main system (just enough to ensure  an air
pocket at the top of the main reservoir) and go drive the thing up a steep
hill (heavy loading helps to show up leaky head gaskets or cracked heads).
Then back to the shop and sniff at the top of the main tank. Alternately,
you can get a chemical test at your neighborhood NAPA parts store. In this
test you suck air(NOT liquid)from the top of the main tank through a
chemical solution which changes color in the presence of HC. ANY HC at all
noticeable above background count (as little as 10ppm) is a sure sign of the
need to reseal heads.

Of course, the coolant/water ratio is OK, right? 50/50 or so? With too
little coolant you might be getting boiling going on, which is a possible
source of vapor in the system. Checking the actual temperature of the engine
and comparing it with the radiator is also a good idea. Is the radiator
temperature fairly uniform from top to bottom and from one side to the
other, and is in the same ball park with the engine temperature? If the
engine is running around 200f, the radiator might be near 195 at the inlet
and 175 at the outlet, with temperature changing gradually across the face
of the radiator, rather than suddenly dropping from hot to cool(indicating
blockage for example)...

You may not be equipped to carry out his kind of testing yourself, but you
might artfully suggest some of these ideas at your local repair shop...

Good luck!

Coby Smolens, Owner
Valley Wagonworks
VW Bus and Vanagon Repair
1535 Sir Francis Drake Blvd.
San Anselmo, CA 94960
415 457-5628
www.wagonworks.com