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                           Engines-List Digest Archive
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                     Total Messages Posted Tue 08/12/03: 2
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Today's Message Index:
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     1. 09:14 AM - Re: Dual radiators...  (Grant Corriveau)
     2. 02:08 PM - Re: Dual radiators...  (Tracy Crook)
 
 
 
________________________________  Message 1  _____________________________________


Time: 09:14:49 AM PST US
Subject: Re: Engines-List: Dual radiators...
From: Grant Corriveau <grantc@ca.inter.net>

--> Engines-List message posted by: Grant Corriveau <grantc@ca.inter.net>

> From: "Tracy Crook" <lors01@msn.com>

> No hard & fast rule on this but I prefer parallel.  If they are low
> restriction coolers, series can work OK too.  Can't imagine what problems
> would be caused by air from the rads going into the cowl.  Typical temps of
> this air is 130 - 140.  Should be no problem.

Tracy,

Thanks for the reply.  I finally tracked down an intermittant engine problem
to the Hall Effect sensors that were sitting directly behind the rad output.
The epoxy used in them shows signs of heat degradation.  With the additional
heat from exhaust tubes, etc... I just figure the life of all the undercowl
items will be better without this heat.

Also, using autogas, I'm a little more concerned about fuel vaporization in
'boiling' hot fuel lines, carb bowls, etc..

If I take the rads outside somewhere, then I'll also be able to seal the
cowling for a more aerodynamic effect, (while adding the drag of the rads
elsewhere - true - give a little, take a little.)

Thanks again
-- 
Grant Corriveau
C-GHTF / HDS / CAM100 






________________________________  Message 2  _____________________________________


Time: 02:08:00 PM PST US
From: "Tracy Crook" <lors01@msn.com>
Subject: Re: Engines-List: Dual radiators...

--> Engines-List message posted by: "Tracy Crook" <lors01@msn.com>


> --> Engines-List message posted by: Grant Corriveau <grantc@ca.inter.net>
>
> > From: "Tracy Crook" <lors01@msn.com>
>
> > No hard & fast rule on this but I prefer parallel.  If they are low
> > restriction coolers, series can work OK too.  Can't imagine what
problems
> > would be caused by air from the rads going into the cowl.  Typical temps
of
> > this air is 130 - 140.  Should be no problem.
>
> Tracy,
>
> Thanks for the reply.  I finally tracked down an intermittant engine
problem
> to the Hall Effect sensors that were sitting directly behind the rad
output.
> The epoxy used in them shows signs of heat degradation.  With the
additional
> heat from exhaust tubes, etc... I just figure the life of all the
undercowl
> items will be better without this heat.
>
> Also, using autogas, I'm a little more concerned about fuel vaporization
in
> 'boiling' hot fuel lines, carb bowls, etc..
>
> If I take the rads outside somewhere, then I'll also be able to seal the
> cowling for a more aerodynamic effect, (while adding the drag of the rads
> elsewhere - true - give a little, take a little.)
>
> Thanks again
> -- 
> Grant Corriveau

The main source of under cowl heat problems is often heat from the exhaust
system, as you mentioned.  The air from the rads is often the only thing
holding temps down under the cowl.  If you are successful in sealing the
cowl for better aerodynamics, my guess is that the problem will get worse
instead of better.  But that's just my guess.  Let us know how it goes.

Tracy Crook