But is that a fair assumption? Maybe the pump *does* move enough coolant
on a Vanagon with a nice clean radiator and otherwise well-functioning
cooling system. It might be easier to fix what may be not working
properly first.

My Vanagon will cycle the fan on at idle on hot days...like when I am in
heavy traffic. As soon as the fan comes on, I can watch the temp gauge
drop down. That leads me to beleive that the pump produces anough flow,
and that the fan is compensating for the lack of forward motion forcing
air through the radiator.

Maybe a good test would be to find a incredibly hot day on a mountain (I
know, unlikely at high elevations) and coast down the road in nuetral
with the engine idling while watching the temp gauge.....

> When a vanagon idles, temp goes
>up, fan cycles on to cool it, but at idle the water pump does not seem
to
>move the volume of coolant from the motor to the rad at a fast enough
rate
>for effecient cooling.

Tom Carrington
tcarrington@relitech.com
http://volksweb.relitech.com
85 Vanagon Crew Cab
82 Westy diesel=>gas conversion
65 Notchback

> -----Original Message-----
> From: jimkim [SMTP:jimkim@INTERGATE.BC.CA]
> Sent: Wednesday, August 18, 1999 12:24 PM
> To:   vanagon@GERRY.VANAGON.COM
> Subject:      Re: bad mechanic???
>
> While we're on the topic of overheating at idle I'd like to bring up
> something I've been thinking about lately.  When a vanagon idles, temp
> goes
> up, fan cycles on to cool it, but at idle the water pump does not seem
> to
> move the volume of coolant from the motor to the rad at a fast enough
> rate
> for effecient cooling.  Perhaps I have to much time on my hands but
> I've
> thought about a clutched two speed pulley for the water pump that
> would in
> effect double the flow rate at idle. Is such a thing thechnicaly
> feasible?
> Thinking aloud Jim.