>
> runway without waiting and start the roll with 180-190F I'm happy 
>
> camper. But if I have to wait behind few planes, I have to takeoff
>
>
> with 200-210F and very soon at 1000 feet start pulling the power
> back 
>
> at 220F. I'm installing misting system like Tracy. Today bought
> the 
>
> pump, but have not installed it yet.
>
> In my short hours in cruise I see 160F water and 137-140F oil
> temps. 
>
> My goal is to do something for the ground an takeoff cooling.
>
> Buly
>
> CZ MK-IV 13B Cosmo NA
>
>
>
> Buly;
>
>
>
> With a pusher, ground cooling is a bit tougher.  Although the negative
> pressure created by the prop would keep my coolant temps down OK
> when OAT
> was 60, at higher temps my results were like yours.  I installed a
> SPAL 10"
> high performance fan on the inside of my rad.
> <http://www.jaycorptech.com/showproduct.aspx?productid=11&categoryid=2>
> http://www.jaycorptech.com/showproduct.aspx?productid=11&categoryid=2 .
>
>
>
> I can now pretty much taxi and wait at idle indefinitely and keep the
> coolant at 190F or less.  That also keeps the oil temps under
> about 200F,
> even though the fan provides no additional air flow for the oil
> cooler.  I
> typically turn on the fan somewhere during taxi, and turn it off
> as I'm
> cleared onto the runway.  It alleviated the anxiety of ground
> operations on
> a warm day.
>
>
>
> I also tried a water spray system on the oil cooler for ground
> operations,but for whatever reason did not find it to be very
> effective.  I think the
> reason is the fins and tubes are relatively vertical, and the
> water was not
> well misted so much of it would run through without evaporating. 
>
>
>
> Al

Hot operations on the ground are all an issue for us 'non-turbine' aircraft. I had fun getting out of LAS last Sunday and sat on the ground idling for 1hr-47min. Even in the C-414A I drive the oil temp's were uncomfortably high [not because it was overly hot either, as it was only ~65deg F]. The main issue I find w/ ground operations is usually your sitting on the taxi way w/ a tail wind, which further reduces your cooling ability, in my case I had to turn parrallel to the runway on the hold short line so I could get some airflow to cool the engines back down before takeoff. This type of situation may effect the ability of an evaoporator style secondary cooling system.. due to lack of airflow? The fan is a great idea, however there must be some drag or cooling penalty to pay while in the air? Al, have you made more changes to your "through the wing" cooling system or are you still using/experimenting w/ it?

As always, everything is a compromise...

Jarrett