On Wed, 9 Oct 2002, Malcolm Stebbins wrote:

> Also I have found that if the engine is at normal working temps, there
> is no need to rev the engine, the 'normal' pressure in the coolant
> system is enough to force air up through the loosened coolant bolt
> threads.

I always figured the reason for revving it was to get the water pump
spinning faster and hopefully drive any air trapped in the engine up
to the radiator.  The cooling system forms a big U from a side profile,
with the engine and radiator the high points.

             _ _
  __ _ _   _| | |  | David M. Brodbeck (N8SRE)              Ypsilanti, MI
 / _` | | | | | |  +-----------------------------------------------------
| (_| | |_| | | | @ cyberspace.org
 \__, |\__,_|_|_| "I think the brilliant aspect of the Bush speech last
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