----- Original Message -----
From: <13brv3@mchsi.com>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Monday, May 19, 2003 7:36 PM
Subject: [FlyRotary] Re: coolant / thermostat



Actually, the engine cools fine on the ground without the thermostat as it
does have a BIG fan out front.

===>  Ed, does it cool well enough to do extended ground runs at high power,
or just well enough to taxi and run-up before takeoff ?  I'm still debating
a bit about installing the monster cooling fan that I have.

Yes, it does Rusty.  However, there is a condition, when I am doing extended
high power run ups I take off the top of the cowl and remove my radiator air
intake plenums from the front of each radiator.  I have them attached with
hinge halfs and simple pull two pins and the plenum comes off (about 30
second job - after you get the cowl off).  I general do not run the engine
full throttle on the ground for over 5 minutes regardless, just no real
need.

I do not have any problem (even on 100 F days) for taxi and run-up before
take off, however, if I tried a full power run up under those conditions, I
would see coolant red line in about 2-3 minutes (thats a lot of time at full
throttle on the ground though).  Even on those days, a max power (is there
any other type)  take-off/climb-out at max gross weight and I might see
210-220F.  Once in my cruise climb (120MPH IAS) mode, the temps back off to
190-200F (on 100F day) even thought the rpm increases to 5600-5800 rpm.   My
coolant and oil temps stay with 5-8F of each other at whatever the operating
temp happens to be in that flight mode at the time - with the oil being the
higher of the two.

Keep in mind I do have a large bottom cowling opening (about twice normal
width) and louvers on both sides of cowling.  I know these contribute to
better ground cooling.

FWIW

Ed