Chris;
For every challenge we overcome, we get
to enjoy the satisfaction. Man, you’re having lots of satisfaction
opportunities!
All other things being normal, my experience
would suggest that getting to 210 or 220 should not be a problem. During
initial testing, I had run my 20B temps to those levels a number of times. No issue.
My concern would be whether or not the
air was purged – or that the temp read out was not correct.
My cooling system bleeds out well, but
it does take at least one run up to temp, and then some added coolant. On
one occasion I had pumped air into the system to pressurize for leak test, and
then forgot to purge that out before making some ‘tuning’ runs on
the ground. Before the temp read over 200, I heard the thumping sound of boiling.
Yikes! Apparently air at the temp pickup. Even that did not result in any
coolant leaks in the housings.
I recalibrated the temp channel on the
EM2, had to change from the default numbers to get a correct reading. If
you haven’t already checked calibration, it may be worth it. The thermister
is non-linear, so calibrate to a low end temp of about 130, and high end at 210
– or whatever your local boiling point is. Using a measured temp water
container is most accurate. I then checked my temp gun (pyrometer) on a
spot of flat black paint at the pump outlet to double check.
Hang in there, buddy!
Al G
-----Original Message-----
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Christopher Barber
Sent: Sunday, January 25, 2009
10:41 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Frying pan
into the fire....Arrgh
Perhaps one day I will post with
good news. However, today is not the day. I have really been having some
fun as I move my project from "proof of concept mode" to "flight
prep mode". The engine and wires have been my focus since I had to
rebuild the strakes in my Velocity following my Jeffco failure. (BTW, I
may have discovered the reason for my Jeffco failure...more on that later).
Since I have seemingly gotten
most my electrical gremlins tamed as in the engine running, the alternators
charging and lights working properly, I was gonna start to actually hook up my
Dynon D-100, radios, GPS's and audio panel today. I was also gonna take
out my EC2 and EM2 to send to Tracy to check out one last time (my EM2
backlight stopped working so I figured I would send it all in now while I tied
up loose ends).
Since I was about to send my
computers in and would not be able to run the engine for a while I couldn't
resist pushing the plane out of the hangar and crank her up. She started
up as expected. I taxied around a bit making my "airplane" into
a loud and expensive "go-kart". I shut down after a few minutes
as the temps started to rise.
I let the bird sit for a bit and
wanted to restart it. Hmmm, not starting. Hmmmm. Let is sit a
bit more. Try again. Still no joy. I sat there for a minute and
remembered it was a bit difficult to start a second time the last couple of
times I ran the engine. UHOH! When I had to build this engine it
was premised by the old engine not wanting to start after an initial
run. The first engine got too hot and was leaking coolant into the rotor
housings.
I took a big breath and went back to
the exhaust.....there was a bit of dirty liquid at the exhaust tip.
Damn. Ok, take a deeper breath and be a man (no offense Chrissi...I am a
man<g>) and go remove a sparkplug and take a look. Sure enough I
removed the leading plug of rotor two and it had a bit of liquid. I hand
turned the prop and steamy liquid blew out the hole. Damn-it, damn-it
damn-it! Coolant in the housing. Checked the front rotor and same
thing, but less liquid. Damn.
Ok, when this happened to my rebuilt
first engine I blamed myself as I was in a serious learning curve. I ran
it hot without a prop, too hot with a prop and without proper
sensors. I really should have been surprised if I didn't fry it.
So, when it failed it gave me an excuse to buy new housings, end and center
plates etc and build what was/is essentially a new engine. I TOOK EXTREME
care as to not to ever let it get too hot. I would shut it down if it got
between 210 and 220. ONE TIME it got to about 225 degrees before I shut
it down and that was only for a matter of couple of seconds. None the
less something has happened to cause coolant to enter the rotor housings again.
I used what were advertised as "beefed up" O rings purchased from
Pineapple racing (kinda as a thanks to their rotaryengine illustrated
website). It is my understanding if that if the engine gets too hot these
"O" rings fail and let coolant seep through. Oh, I sooooooo
hope it is just the "O" rings and the hardware was spared. All
the hardware is new and professionally ported by Mazdatrix to a medium street
port...I really was developing some power.....
I spoke with my engineer friend,
Blaine, who owns a couple of aviation business with R&D as a major factor
as well as building a Soob/Eggenfielder RV-7 and he and I are gonna look
into what I missed. Verify that my sensors are working properly, check
the cooling system for proper flow again among other things. Very
frustrating though. I am, however, getting very good at removing my
engine from the plane. I had it off and sitting on the work table in only
about an hour. I am not gonna crack the engine open yet until I can get
Blaine over for some joint brain duty. On a positive note, there are a
number of things at the "firewall aft" that I need to address, this
is giving me the perfect opportunity to do so. They will be much easier
to improve with the engine off.
Now to resign myself to yet another
engine build as we determine the why.
And, as to another
"why". I may have determined why my Jeffco failed in my fuel
strakes. As loyal fans may remember I had to remove all the old
epoxy/Jeffco from my strakes and redo them completely a couple of months ago
due to the Jeffco peeling away. Well, as I was poking around the hangar
looking for something I had placed as to be able to find it easy
later......yeah, right, I came across my old Jeffco bottles. Hmmmm, the
Hardener is labeled 3191 and the Resin is labeled 9700. Now, I remember
that when I ordered it a few years ago it was 9700. I remember
specifically as when I first ordered from AS&S they sent the wrong stuff
and I returned it for the 9700. THIS time I ordered new Jeffco, but choose
not to use it and just use straight EZpoxy for my strakes, however, in the new
order BOTH the Hardener AND the Resin were labeled 9700. My current
thought is that I used the Hardener that AS&S supplied with the kit
assuming (yeah, bad Chris for assuming) that it was the correct one to use with
the 9700 Resin....which is what I knew to be the proper number. It was
not until the new order arrived a few months ago and I saw both the hardener
and resin are both 9700 and finding the original bottles from a few years ago
that I would have ever discovered a problem.
I intend to send a email to the
company that bought Jeffco and see if they can verify this conclusion.
As always y'all's insight,
commentary, Wild ass guesses and demeaning remarks are anticipated and
relished. Please though, no gee Chris, you sure seem to be having a lot
of problems. Yes and No...I just like to share more <g>. In
the tradition of John Slade, share it all, it can only help. Heck, this is the
time to break things. Much easier to deal with now in my own hangar and
not on some deserted strip or worse yet, in the air....even if my wallet is
screaming.
So, the fun starts when???????? :-)