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Ok, taking my own advise of not overlooking the
basics, I got out to the hangar today and started checking for leaks in the
intake. I could find none. Soooooo, I started retracing my steps of the
last several days. Hmmmm, what did I do last? I set the timing by
looking in the sparkplug holes to find the apex seals. Maybe I didn't get
the plug wires set properly....no, they are on firmly....oh, uh oh.....the wires
on on correctly.....but the REAR PLUGS were LOOOOSE. Bam, tightened up the
plugs and the engine started way easier and smoother (gee, ya think), but still
running with not mixture knob.
My buddy Blaine Streeter, my aviation company
owner/engineer who is building an RV-7 with an Eggenfeldner Subie
engine(even though he is very pro rotary and has worked with Mistral and stated
if he was doing it again, he would likely choose the Mistral) came by the hangar
to help out.
I described the problem with the knob and I stated
I checked wires, d-subs and even the knob itself. He repeated the metered check
of the knob. He took a look at the PCM, asked for a magnifying glass and
stated I had a bad "trace" to the knob. Yep, he showed me the
problem. We got out a soldering iron, repaired the trace and installed the
PCM. Zoom zoom zoom, the rotary came to life easier than ever. Not
perfect yet, but WAAAAAY better. It was getting late so after discussing
various items with his learned input we called it a night VERY
GOOD progress night while focusing on the basics. I now need to get my
timing down better with a timing light and follow a few other small, but
significant observations and get this thing moving forward.
Thanks guys, I would hate to think about doing any
of this without y'all.
All the best,
Chris
----- Original Message -----
Sent: Friday, June 13, 2008 12:37
PM
Subject: [FlyRotary] Re: First Start -
AGAIN
Chris,
It looks like Tracy has given you great counsel (as usual).
For the Mixture problem there is one step further that you could test
which is to check if the voltage changes at Pin 26 on the EC2 37 pin
connector.when you change the Mixture knob setting. Even if the wire from the
control module to the EC2 checks good and Tracy's test below
is successful there still could be a problem on the control module
itself.
On my system I was having trouble setting the mixture and found a
cold
solder joint causing intermittent connection on one of the Mixture
controls leads.
I would caution anyone mounting the control module of the EC2 to their
instrument panel to secure it with the proper standoffs and screws (not
supplied with the system) in addition to the nuts that attach the Program and
Mixture controls to the instrument panel.
If this is not done then there is tension on the controls and their
leads which may cause them to eventually disconnect.
This would be a very BAD thing if it occurs in flight.
I did alert Tracy to this issue and I believe that he made a mention of
it on his website (under Service alerts) but I do not believe that the
installation guide makes specific mention of stress relief on the control
module and its associated wiring.
Jim Maher
Tracy Crook <tracy@rotaryaviation.com>
wrote:
Only time to hit the high points before hitting the road (wish I were
flying :) Main thing is, once you have identified a problem,
don't keep flogging away at other symptoms until you have fixed the one at
hand. I am assuming your analysis of the non responding mixture
control is correct. Mike and John may be correct when they
say that you could be so far out of tune that the mixture control is not
having the expected effect, but this is rare.
BUT, all the symptoms you are relating scream that the mixture control
is not connected to the EC2. This leaves a floating voltage to
the EC2 so the mixture will drift around like a ship without a rudder.
This makes ANY attempt to tune or fix other problems a waste of time and
counterproductive. Fix the mixture control problem or determine
whether it really is a problem befor doing anything else (with the
engine).
To test the mixture control itself, with the power on, and the panel
connected to the EC2 measure the voltage at the top pin of the
pot. It should vary from zero when fully CCW to +5 volts when
fully CW. It should vary smoothly when between these extreams.
Don't short anything out during this test, use a little spring clip or
insulated aligator clip when taping into stuff liker this. Don't just
jam a meter probe in there which can easily slip and short things out.
(been there, done that).
Last hint. The mixture * CAN NOT * make the engine run faster
than normal idle. You have an air leak somewhere. Find it.
I assume it is not the idle setting on the TB? But do this after the
mixture control has been fixed.
Tracy
On Thu, Jun 12, 2008 at 10:58 PM, Christopher Barber
< CBarber@texasattorney.net>
wrote:
I have got my work cut out for me. I went out
to the hangar. The good news is the engine not only started, but
started a all my few attempts. If you remember from previous
episodes my old engine (the one that leaked coolant into the chambers)
would tend to start once and only once a day (or several hours time
past).
My newly built engine is starting
consistently. I played around with the timing a bit and hopped the
CAS a tooth to get it to align a bit more in the center of its turning
area. It didn't seem to make much of a difference yet, however, I am still
having trouble with the Mixture Knob. It is not making a difference for
the A or B controller. I have checked the d-sub connection on the
PCM and the wire from ECU pin 26 to PCM pin 15 and they all seem to check
fine. I will need to climb in the back of the plane to check the
connection at the ECU but I ran out of time tonight.
I am currently getting some strange actions
from the computer. I can start the engine with B if the cold start
switch is on. I switch to A and it want to die, turn of the cold
start switch and it smoothes out nicely. If I start in A, it needs
the CSS off. If I started in one and switch to other, it seems to
want to die so I switch back, shut down then restart in the other position
and it will want to die when changed. Also, when in B, I killed the
primaries and it kept running....cut the secondary's and it wanted to
die. When I tried it in A, it would want to die when the primaries
were shut down. The engine is running pretty fast too. About
1700 rpm ish. I have checked for intake leaks in a preliminary
manner and will do so more when I get to the hangar
again. I don't know how much of this may be attributed to
the mixture control not working. I also seem to be getting oil flow,
but I am having some problems with my oil pressure sensor...sure
don't want to be running with bad oil pressure. So, this is some bad with
the good.
Gawd, I hate consistent inconsistency.
;0
I am a bit frustrated,buy hey, I got the dang
engine to actually run based on me building it with new parts with a
medium street port. Yeah, I want to get past this stage, but at
least I am moving forward.......kinda. I think my next step will be
to verify all my wire runs. I broke one of our cardinal rules and I
changed more than just one thing at a time. I re-terminated some of
the wires due to there extreme length. I had to do something while I
waited for parts from Mazdatrix and Tracy. <g> On that note,
as of now, my PSRU does not seem to be leaking any oil.
So, what say y'all??????
All the best,
Chris
Sent: Wednesday, June 11, 2008
8:29 AM
Subject: [FlyRotary] Re: First
Start - AGAIN
Never seen an EM2 freeze up but then I've never left it running
over night (not that it should hurt anything).
When you say that the mixture knob made no difference, did you
mean that the mixture monitor did not respond or that the engine did
not respond to a change in mixture (egt change, sound of engine,
etc). Assuming for the moment that the engine did not
respond, the first thing to try is the backup controller. Did
you try it? Did it act the same? If it did act the
same, it is VERY unlikely that two controllers have failed in the same
way at the same moment in time. (have you ever heard me say this
before? :>) The obvious place to start is the wiring
between front panel and EC2. Specifically the wire from pin 26
on EC2 to pin 15 on the front panel. (see instructions)
Are they connected? Are they shorted to ground?
Tracy (Colorado bound)
On Tue, Jun 10, 2008 at 12:46 PM, Christopher
Barber < CBarber@texasattorney.net> wrote:
Ahhh, the joys of engine development.
After fiddling with getting the timing set (thanks to y'all for this
info) I was able to start my new engine. I ran it for a
few minutes while checking for leaks etc. I was thrilled it
started again.....however........
I found one leak coming from the top of
the engine where I had a heater hose inlet sealed off. It was
tapped out earlier but only clamped closed so I installed a bolt
with some sealant on it and recovered it with a end hose piece and
clamped it shut. This proved a better choice.
The larger concerns are this.
When the engine started the Engine Monitor was on, and I kept a
diligent eye on it. After a couple of glances at it in the cabin
while looking at the engine I realized that the monitor was not
"monitoring". I grabbed my handheld laser temp
monitor and pointed it at the engine and temp was still
ok. At first I just noticed the RPM was not regersting (my
first thought was I was gonna get the NOP signal), then that the
temp was not moving. After shut down, I turned the
monitor off and back on and instantly the monitor started working
again. Hmmmmmm. The monitor was mistakenly left on
overnight and I am guessing it "froze up" during this time, but I
would have not thought leaving it on would have done this. It
also worked on my three subsequent short starts. Of course my
hope is that this was an anomaly, but will stay aware that
it did happen.
However the biggest problems follows.
When the engine started it was running a little fast, but did not
seem too bad and I throttled back and it slowed a bit. When I
noticed that the monitor was not processing data I grabbed
the mixture knob and turned it to slow the engine and to see if
it made any difference. Damn, the mixture knob was not doing
ANYTHING. NOTHING. Turning it from left to
right made no difference. Damnit. I cut
the fuel at this point, too many issues. BTW, the prime
function, cold start switch and A/B inputs all seemed to work
and would make a difference when operated. But not the mixture
knob.
After letting the engine cool
a while (the temps did rise pretty fast per my hand
held laser temp gage and I was pushing 220 after several
minutes on a hot/humid Houston summer day) I restarted to see if the
engine monitor was working. It was. However, the mixture
know was not. I re-checked the other inputs and they all
worked. The engine was running pretty rough......gee, the
mixture actually makes a difference <g>.
After shut down I disconnected the
batteries (I have installed master battery cut-offs) and
then the control module and ECU and checked the wires between
the two. This was just a quick continuity check and the wire
was good. I then took a meter and in my non electrician mode
attempted to check the actual knob. I place leads
on the two prongs that seem to be soldered to the control board
and turned the knob. The numbers changed up and down as
expected when I turned the know....so it seems that the knob itself
is not the culprit, and the wire seems ok. What else should I
check and/or try? I kinda need the mixture control
to work.
Is there a way to test to to test to
determine if this knob is actually doing anything when the engine is
not running??????
Of course my timing sucks as Tracy is
about to hit Colorado.. So any solutions y'all may be able to
provide should prove especially useful.
I anxiously await y'alls
response.
Maybe I should just go ride my loud
motorcycle to think thinks through. <g>
Thanks again.
All the best,
Chris Barber
Houston
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