Date:         Sun, 7 Sep 2003 22:46:58 -0500
Reply-To:     John Rodgers <j_rodgers@CHARTER.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         John Rodgers <j_rodgers@CHARTER.NET>
Subject:      Re: Coolant leak questions
Comments: To: maurio11@COMCAST.NET
In-Reply-To:  <001f01c3758b$7c812c10$0100a8c0@yourze8cxvr8tt>
Content-Type: text/plain; charset=us-ascii; format=flowed

Though the Bentley says raise the front of the van to bleed the cooling
system, my mechanic raised the rear end to bleed the cooling system. By
doing this, all trapped gases worked their way out of the system through
the top of the expansion tank. The process seemed to have worked really
well, as I have never hand any trapped air problems.

You mentioned a nubbin at the top of the expansion that you suspected
was a little vent........

Sorry, but THERE SHOULD BE NO VENT!!

The expanding coolant should properly flow through the tank pressure cap
and into the over flow tank. When the coolant begins to cool, back
siphon action will draw the coolant out of the over flow tank into the
over flow tube and back into the expansion tank. If there is a vent, the
pressure cap will not function correctly and you will lose your coolant
through the vent hole.

Regards,

John Rodgers
88 GL Driver

David Maurio wrote:

>Since I put the tach in I ran a couple of tests on my coolant leak problem.
>
>I followed the Bentley instructions, parked the van on an incline, front of
>van about 4" higher than back.  Opened the front bleeder valve and the rear
>bleeder valve, ran the van at 2000 rpm until coolant started flowing freely
>from front.  Closed front valve, waited about 10 minutes and still nothing
>from rear bleeder valve, (both coolant hoses below the van were hot, and so
>was the hose that the rear bleeder valve is on) so I removed my penny from
>the throttle and let it go back to idle, as soon as it went down from
>2000rpm I watched the coolant level in the expansion tank start to
>skyrocket! Still nothing from the rear bleeder valve.  It started
>overflowing from the top of the expansion tank, there's a little nubbin at
>the very top of the expansion tank which I suspect is a vent, and that's
>where the coolant leak is coming from.  This all happened within about a
>minute of dropping the rpm's from 2k to idle...  The coolant was bubbling as
>I watched it rush back into the coolant tank.
>
>Any suggestions or ideas?
>
>Thanks,
>David / NJ
>85 Wolfsberg Westy "Beatrix"
>http://home.comcast.net/~maurio11/index.htm
>
>
>