Jerry Hey wrote:

I finished the swirl pot yesterday.   All that

remains for the

cooling
system is the overflow tank which I think I will

make out of

welded

aluminum.  Is there any problem with having it

fill and empty

from

the
bottom?    Jerry

Nice photograph Jerry. What is that oil cooler

doing near the

firewall?

That is where mine was originally. It did not work!
Ian RV6A.

I'll reserve judgment until I see what the scoop

and duct look like

:-)

Paul Lamar

I am planning to pipe the air in from the front of the cowl,

probably

3" round inlet.      Scat to intake plenum.   Air

exhausts  at

bottom

of cowl.

I would welcome anyone's recommendations for fitting

an air cleaner

and

intake.

    Jerry

That sounds good Jerry. Be sure and make the transition

from three inch

round SCAT to the cooler bell shaped.
Here are the coordinates again for the new guys.

Paul Lamar

Jerry,
I don't think that 3" is nearly large enough.  You will

probalby need

about 25 sq. in. of intake area (according to Fred Morino)

for the oil

cooling.  The 3" is a really small duct.  Take a look at

the following

numbers:

3" = 7.069
4" = 12.57
5" = 19.63
5.5" = 23.76
6" = 28.27

FWIW, I'm not flying yet.

Ken P.

Ken Powell
kenpowell@aristotle.net

Good point Ken. I missed that.

Paul Lamar

My original oil cooler location (Earl cooler) was within

12" of the firewall

and with the initial 3" dia duct temps went to over 240F on

first flight.

Later and even with a better plenum and  5" dia duct

cooling was marginal.

Could have been the oil cooler or the location or a poor

plenum, but I did

not get effective oil cooling until I went back to the

stock mazda oil

cooler and moved it up under the spinner.  FWIW

Ed Anderson

I think Ed gave up too soon as his transition from round duct
to rectangular
cooler was less than optimum. Also I suspect his cooler was
too close to the
firewall to allow a free flow of air out the back side. I am
still not convinced
that a configuration like that can not be made to work. I
agree with Ed that
it could also have been the Earl's oil cooler as they have a bad rep.

Here is a set of curves on Earl's oil coolers. I need to
convert some of these
numbers and compare them to the new Stewart Warner oil cooler
data we now have.
This will give us some useful air side clues.

Chuck Dunlap had his stock cooler on the firewall with a
straight metal duct in from
the stock cowl opening. Seemed to work. How is it working
these days Chuck?
Are you happy with it?

Paul Lamar

It works fine in cool weather. It is marginal above 90F OAT in a climb. I
flew today 61F OAT and the max oil temp was 190F after full power takeoff
and 100MPH climb to 7500FT. My inlet is one side of Van's nostril intake 21
sq. in. but it reduces to about 10 sq. in at the oilcooler duct due to
interference with the water pump inlet. I will modify the water pump when I
install a new engine, then I can improve the duct. Jerry, I think you will
be alright if your first flight is in cold weather and if you can run full
power on the ground for 10 minutes without the oil overheating. I think you
will find you need more than 3" duct in warm weather.

Chuck Dunlap

 
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