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Chris..
For troubleshooting reasons AND continuity, when you discuss power settings, remember there is more to a power setting than just RPM.
With an adjustable pitch prop, Manifold pressure (boost gauge in cars) is just as important of a value when discussing power settings. Or to put it another way... RPM by itself means NOTHING and has practically no value with regards to power settings in a variable pitch setup.
Remember our first couple starts (without the EM2 connected...) how it ran and ran even when the fuel was cut off.. when we finally hooked up the EM2, we discovered that there was an air leak in the manifold pressure sensor tubing causing the EC2 to think the throttle was wide open, and provide fuel with respect to a wide open throttle.
For folks to be able to troubleshoot you here, and you give engine responses with regards to RPM.... you also need to include the MP as well. 25 or higher MP is a condition where the EC2 thinks the throttle is wide open (in our normally aspirated engine.. sea level pressure is around 29 or 30 with engine off). 14 or less in our installation has tended to be when the throttle was closed and there was no MP tubing leak. Low MP means low power, and less fuel being introduced. We can have low MP and high RPM and still have low power.
My point.. if we have a manifold pressure tubing leak again, the leaning the mixture knob is like trying to close 1 faucet, when the fuel is flowing at a rate of 1000 faucets... wont have a measureable effect.
Can you smell fuel after your runs? Does it seem overrich.. soot staining on the ground where the exhaust hits the pavement.. shooting flame during start?
Were all the sensors calibrated before starting (temps, pressures..). Without calibration, there really isn't any way you can trust what they are telling you. If you are getting flakey readings, remember the sensors generally need to be grounded too.
Sounds like the programs between a and b are extremely different. One is very rich compared to the other.. so getting it started on one can be done, as well as the other, but when you switch... its too big of a change and the motor stumbles. perhaps a reset to defaults and then start tuning again is in order..
Need to get the electric gremlins sorted out before running it again..Gremlins will cause you to have trouble while trying to auto tune..
I'd hate to see a brand new engine bite it..
Enjoy your weekend,
Going to the ROT rally in Austin
Dave
Christopher Barber 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
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*From:* Tracy Crook <mailto:tracy@rotaryaviation.com>
*To:* Rotary motors in aircraft
<mailto:flyrotary@lancaironline.net>
*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 <mailto: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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