Re: [A/S] cooling capacity

[Jim Dunmyer <jdunmyer@xxxxxxxxxxx>]

Jon,
 I don't disagree that removing the thermostat may cause inadaquet
cooling, but the reason is not because of the coolant 'not remaining in
the block long enough to pull the heat out'. That just isn't the way
physics work.

Look at the very old cars and tractors, most of them had "thermosyphon"
cooling, with large radiator connections and NO water pump. That
arrangement certainly allows the coolant plenty of time to 'pull the
heat out', yet was abandoned long ago in favor of water pumps and much
higher flow rates.

What does happen with 'excessive' coolant flow is cavitation. This can
be thought of as similar to giving your car too much throttle on
take-off, causing the wheels to spin. When coolant is flowing through
the block at a too-high rate, it will sometimes swirl and bubble in
localized areas in the block and head(s), and bubbles will not transfer
heat.

We both agree that it's not necessarily a good idea to second-guess the
manufacturer of the vehicle, they've spent no small amount of money to
engineer things 'just so'. A larger radiator won't hurt because the
thermostat should keep the temperature up where it should be for
efficient engine operation, but will give extra cooling capacity when
needed during hot weather or sustained high power operation.

                                            <<Jim>>