Nigel,

People have been using their heaters (water-cooled applications) for that
very purpose, probably since the first day they started putting radiators in
cars. The heater core is essentially a miniature radiator. Coupled with the
fan, they can definitely bring your engine temps down.

Ben T
San Francisco
 <A HREF="http://hometown.aol.com/bentbtstr8/myhomepage/index.html">Vanagon
Cafe</A>