That's intriguing.
Not doubting it's possible, but what would cause it?
Only 2 things I can think of is loose impeller or worn impeller.
If the impeller is loose and slipping at idle, imagine what's happening at
full throttle... I would think failure would follow quickly.
Other option is worn or eroded.  Is this common with water pumps?
I thought the bearings leaked and failed first usually.

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Don Spence
Sent: Wednesday, January 06, 2010 1:13 PM
To: vanagon@GERRY.VANAGON.COM
Subject: No heat at stoplights.

Tired water pump.

On 6-Jan-10, at 8:38 AM, Automatic digest processor wrote:

> No heat at stoplights.