Re: Cooling

[jlandry@domain.elided (John A. Landry)]

The aliens commander decided Tom Mandera <tsm1@domain.elided> would make a
perfect specimen for dissection, and he yelled...

>So long as my radiator has had coolant, I haven't had a cooling problem
>on my '77 SII w/ 72 304A.  however, after having the radiator flushed
>and two damaged tubes replaced, *AND* cleaning out the plugged overflow
>vent tube, I'm starting to see problems.
[snip]

Tom,

Just out of curiosity, is there anything strange about the speed of your
water pump we should know about?  I mean, have you done anything weird with
the pullies or anything?  Your problem sounds like you're simply not
getting enough circulation of the coolant at idle.

Also, did you check the pump impeller blade to the pump housing clearance
when you installed the pump?  I suppose it's possible the gap between the
pump blades and the housing is so great as to cause decreased efficiency of
the pump at low speeds.  A thick pump gasket can aggravate this problem.

Possibly all of the work on the radiator and coolant draining dislodged
some crud in the cooling system which is inhibiting flow somehow, but since
it only happens at idle, I'm inclined not to think so.  

It can't hurt to put in one of the correct Robert-Shaw type thermostats
either.  If it doesn't have that style now, you'll be surprised how much it
can boost the cooling system efficiency.  This thermostat helps to properly
block off the bypass hose... especially critical at low coolant flows... to
force more coolant through the radiator.

Regards,

John L.
-------------------------------------------------------------------------- 
jlandry AT halcyon DOT com      | 
Conservative Libertarian        |  "The road to  tyranny, we must never
Life Member of the NRA          |   forget, begins with the destruction
WA Arms Collectors              |   of the truth."
Commercial Helicopter - Inst.   |                     William J. Clinton
http://www.halcyon.com/jlandry/ |    10-15-95, speech at the Univ. of CT