Scott,
Thanks for the lead. I'll check with
Paul.
As Dave alluded to, I "tinkered" a lot before the
first flight. Like you I built, discarded, then rebuilt my cooling system.
Unlike you I did it 4 times before I ever ran the engine. I guess I can say in
hindsight that it was worth the effort because cooling is the one problem I
havent had.
All my plumbing is Earls. It is possible to
misassemble. The problem occurred while running on the left tank and cleared
immediately upon switching tanks. There's only one hose in my system that is
unique to the left tank so that should be easy to check. Thanks for the
tip.
Mike Wills
Sent: Sunday, April 18, 2010 9:10 AM
Subject: [FlyRotary] Re: cooling for ground runs
Dave & Mike;
Thanks for the kind words of encouragement. The lower intake manifold
casting was an offering from Paul Lamar, I don't know if he still sells them. I
also bought his injector mount tubes...which were a bust for me. Heck, I
was just starting and still had to conceptualize the whole thing. Although I've
met PL a couple of times at the Arlington Airshow, and bought his nice intake
casting, I couldn't get much benefit from his site. Maybe it's just
me. Mike;
I totally understand the 'tinker factor'. I've changed many concepts (not
just parts) on my plane. I probably should not have built a tuned intake and
also a turbo. I saw a turbo normalized 13b set up by Dave Adkins (he's in
my EAA chapter) that has a very brief intake manifold...nice & light. But
choices made earlier dictate what can be done after.
As for the loss of fuel pressure while in flight,(!!!) You might consider
the possibility that a fuel hose inner liner was skimmed when assembled to the
fitting (aeroquip style) and left a flap on the inside that could be pulled by
fuel flow to close off the hose. Sakskyranch warns of this, and a Cessna 205 at
my local field force landed on the highway once because of it.
-----Original
Message----- From: David Leonard <wdleonard@gmail.com> To: Rotary
motors in aircraft <flyrotary@lancaironline.net> Sent: Sat, Apr 17,
2010 11:05 pm Subject: [FlyRotary] Re: cooling for ground runs
Mike,
Repeat after me: "I will not rebuild unnecessarily, I will fly
instead." "I will not rebuild unnecessarily, I will fly instead." "I will not
rebuild unnecessarily, I will fly instead." "I will not rebuild unnecessarily, I
will fly instead."
Lets face it. You tinkered with that thing for many years. If
you were ever going to get it right you would have done it by now. So quit
trying and keep flying. :-)
On Sat, Apr 17, 2010 at 10:51 PM, Mike Wills <rv-4mike@cox.net> wrote:
Scott,
I agree with Dave, that looks great. One picture shows
your intake manifold. Looks like you used a casting for the lower part with a
transition to tubing. Where did you get the casting? Is it a stock Mazda turbo
casting that you cut the top off of? I'd like to do something similar.
Not real happy with my current manifold and would like to rebuild
it.
Mike Wills
Sent: Saturday, April 17, 2010 9:49 PM
Subject: [FlyRotary] Re: cooling for ground runs
Thanks Scott, You are right about what I said and I will
clarify a little. I say if it wont cool on the ground, it wont cool in
the air because when I first started flying I had marginal cooling on the
ground and marginal cooling in the air. At that time I could idle and
taxi indefinitely unless the OAT was above 85 or so, when my taxi times would
be limited to about 30 minutes. cooling in the air was similarly limited
to shallow climbs and less than full power in all but the coolest of
climates. However, Chris may be talking about high power ground runs
which is a different story. A full 5 minutes at full power on the ground
is sure to push the limits of most installations, and a temporary spray bar
fed from a hose is a reasonable thought if you feel the need to do extended
ground runs at or near full power. BTW Scott, I just took another
look at your website and picture. You sure have done very nice
workmanship. I can't wait to see that thing fly! It is guaranteed
to be one of the fastest RV's around. -- David Leonard Turbo
Rotary RV-6 N4VY http://N4VY.RotaryRoster.nethttp://RotaryRoster.net
On Sat, Apr 17, 2010 at 8:55 PM, <shipchief@aol.com> wrote:
Chris & Terria:
I had ground running temp issues at lower power. Dave Leonard told me
that it's important to get it to self cool at low to mid power on the
ground. He said that reliance on sufficient cooling when you come up to
flying speed most likely won't work if it won't self cool on the
ground. I took his advise and redesigned my cooling system, which by the way
looks a lot like yours with major differences being cooler ducting and
cooler orientation. He's a link to my page @ EAA326 site: http://gallery.eaa326.org/main.php?g2_itemId=1727Tracy
has commented that I should have reduced the cross section of my oil cooler
duct more quickly to force the air to uniformly pass thru the oil cooler
core. I applied that thinking to my water cooler which I built next, and it
worked even better than my cardboard and tape trial duct.
What is the engine RPM and % load that you start to have cooling
problems?
Scott
-----Original Message----- From: Chris and Terria < candtmallory@embarqmail.com> To:
Rotary motors in aircraft < flyrotary@lancaironline.net> Sent:
Sat, Apr 17, 2010 10:02 am Subject: [FlyRotary] cooling for ground
runs
Gents,
I am doing the higher power ground runs now, and am
only able to run for about 5 minutes before reaching 195* or so. I’m
looking for ideas on how to extend the time for each ground run. I was
thinking of adding a spray bar like others have discussed. My thought
was to drill some holes in some PVC and connect it to the garden hose.
Then put it in the intake in front of the radiator. I would have to
run the hose out the front and clamp it down so it doesn’t come close to the
prop.
I’m open to all ideas though.
I’ve attached a picture that shows my radiator and duct
work.
Thanks,
Chris
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