Mailing List flyrotary@lancaironline.net Message #57898
From: Mark Steitle <msteitle@gmail.com>
Subject: Re: [FlyRotary] N774CG, RV-10 20B first flight
Date: Wed, 25 Apr 2012 11:12:38 -0500
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Tim,

Well, congrats on your first flight.  It sounds pretty much how my
first flight went.  To fix it, I increased the cowl exit area which
definitely helped.  Then I added a cowl flap which helped even more,
especially during climbout and when operating in very hot temps.  But
the biggest change came when I discovered that my dual-pass oil cooler
was defective, partially bypassing the core.  I replaced it and my oil
temps improved.

As a final move, I installed a Laminova oil/water cooler.  Since I had
excess water cooling vs. oil, this exchanger extracts additional heat
from the oil as well as coupling & equalizing the oil-water temps.  I
no longer have cooling problems.

I'm curious as to why you plan to move the coolant temp sensor to the
radiator return line.  You need to know the max coolant temps, which
you will measure in the engine outlet (leading to radiator).

 Mark S.

On 4/25/12, Tiffanie Holt <coastiefamily4@gmail.com> wrote:
> Well, got up this morning and did the first flight on the RV-10.  OAT
> 55 Degrees at 7000 ft.  Did the taxi to the runway and the water temp
> was 168 and oil was 150.  Everything looked full power in and off we
> went.  She has plenty of power, RPM was 7000, and here comes the
> temps.  I immediatelly turn to down wind at 80kts and the water temp
> came up to 220 and oil at 200.   Turned base and temps still climbing
> still at 80 kts, turned attention to land vise temps.  I landed
> immediately and taxied back to the hangar and the temps peaked at 245
> water and 240 oil.  She got hot, I got boil over once I shut the
> engine down.  I took all the cowls off to help the cooling of the
> engine.  Check everything over, turned the prop and listened for any
> unusual noise, checked the oil and could smell the 2 stroke oil in it,
> which I understand is normal.
>
> She Flew, but not what I expected on temps.  These are the highest
> temps that I have seen so far.  I had 11 hours on ground runs, but I
> did not let water temps get above 205 and oil temp normally stayed at
> 180.
>
> At the hangar, I let the temps get to 180 on water and 160 on oil, I
> filled the expansion tank back up and ensure there was coolant and
> started her back up to see if I had normal readings.  Oil pressure was
> on the rise, oil temp was at 175 and water temp stabilized at 190,
> Just wanted to ensure I did not do damage to the engine and that she
> would start. She was a little hard to start, but started purring like
> a kitten again.  Shut her down, and then started her back up and she
> immediately turn over.
>
> Did not run her much longer, had to shut her down and get to work.
>
> Are there any suggestions or inspections that I will need to do on the
> engine for the high temps?
>
> Things I plan to do before next run:
> 1. Oil Change, Filter Clean: It is time for a cleaning and I can
> inspect the oil.
> 2. Flush the radiator: Ensure everything looks normal
> 3. The highest point in my water system is the expansion tank, but the
> water return is at a level slightly below the expansion tank.  I plan
> to install a fill/bleed valve in it to ensure all the air is out of
> the system.
> 4. Move the Water Temp Sensor from the block to the return line to the
> radiator
> 5. Place the Louvers in the cowling.  I did put the louvers in per
> Van's Plans, but I put then in the cowl to help pull the heat from the
> exhaust system.
> 6. I will also open up the inlet to the Radiator as well.  The
> standard Sam James Cowl has a 4 3/4 inch Diameter opening, I will open
> it up more and give it at try.
>
> Any suggestions would be greatly appreciated.
>
> Tim
>
> --
> Homepage:  http://www.flyrotary.com/
> Archive and UnSub:
> http://mail.lancaironline.net:81/lists/flyrotary/List.html
>
Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster