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Hi Paul,
I've just been thinking. (A most dangerous
exercise for me @ 4:30 am in the morning!). As I mentioned
previously, I don't think the "fan out" had anything to do with the ECU
itself. Reading your posts, it looks like you have got a bit of a
handle on tuning anyway, with mention of running the aircraft up
against your van, and fiddling with the mixture while watching the EGT
etc. I assume you have disabled the rev limiter function on the
Microtech??
From what you tell me, it looks like it's a
nightmare to remove the engine. Seeing you have flown successfully for
over 9 hours already, then the engine obviously has sufficient grunt
to keep the aircraft airbourne. Probably a waste of time & money
getting this engione dyno'd.
So if you are having another engine assembled with
high comp rotors, I'd wait until then. There is no reason why you
couldn't leave the engine plate on the engine though. From what I have
seen, the plate is mounted onto the frame with just 4 mounts?? If
you find a friendly engine dyno place, then do get the new engine
dyno'd. You will then know exactly how many BHP the engine has at what
RPM, and can then probably get the prop size right first go, and as
a bonus, you will have the confience in knowing that the mixtures are
correct.
Anyway, back to the present conundrum.
Many many years ago, when teaching me to diagonse engine faults, an
old mentor once said to me that if an engine has approximately the right amount
of fuel, and a decent fat spark at approximately the right time,
then an engine will run and produce a reasonable amount of power - unless there
is something mechanical wrong with the engine itself.
Rotaries are particularly forgiving in that they
will run on a pretty wide mixture range, and are relatively insensitive to
timing, (except under boosted conditions), and there are only three
basic things that will kill a rotary mechanically - loss of oil (I can see Rusty
nodding his head!), loss of coolant, or swallowing something
solid.
The trick is to now systematically work down
through your "fan out" episode to see why it quit. Whatever you do,
DON'T jump to any conclusions. Assume nothing, and check
everything. Have you tried to start it since? Will it run??
Basically, when I have a problem like this, the first thing I
check is ignition, (because it's easy, and immediately eliminates
50% of the options if I get a jolt from a coil lead!!).
I know this might sound facile, but obviously
if there is no spark, you go and find out why. A blown fuse,
dud relay, loose wire somewhere, faulty switch etc. If
you do have spark, then the problem is most likely fuel supply. Fuel
tank selector first (My mate Ed turned his RV into a glider one time simply
because he didn't have any fuel in one of his tanks!).
I also know of a certain experienced aerobatic
pilot over here who is now in a wheelchair because he didn't have the fuel
selector positively set to the correct tank. The selector was half way
between tanks, and while it had enough fuel supply to do the
"run-up", it didn't flow enough fuel for WOT at take-off. The
ineveitable, happened, the engine quit around 200 ft, he tried to
turn back, it stalled and fell on it's tail, and he's now in a
wheelchair. He also totalled a really nice aircraft.
If there IS fuel in the tank (yeah, yeah,
... I know, I know, ... but it's REALLY easy to check,
and it HAS happened before - remember the historic Boeing
307 Stratoliner that became a submarine in Elliot Bay Seattle?? - so
even the pros are not immune to this!!), and the tank selector is
correctly selected, then filters,
then water in the fuel, then fuel pressure, tank vents,
crimped hoses etc. It's a bit like a game of
20 questions (Ever played "Animal, Vegetable or Mineral"??). The
Name of this game is "Igniton, Fuel, or Mechanical". You try
to eliminate about half of the causes at each step, commencing with the
easiest options.
So don't give up on the EFI just yet. I can
tell you that having played with carburettors for 30+ years, I prefer EFI
anyday. It's a mindset thing. Carburettors also have their
downsides, and are subject to all the same fuel supply issues as
EFI. (Fuel quality, water in the fuel, filters, pumps,
lines, tanks etc) One major one that is a rarity with EFI is
flooding. Ask poor Ken Welter. "Kentucky Fried" his Coot to a crisp
some time ago.
Anyway, that's my little velvet bag full of
Downunder pearls for today.
Cheers,
Leon
----- Original Message -----
Sent: Thursday, February 10, 2005 2:12
AM
Subject: [FlyRotary] Re: To Paul Re:
[FlyRotary] Re: Microtech EFI and Tuning
Hi, Leon thanks for taking the time to go into
such detail (as is customary for you) regarding suggestions for tuning my
engine, etc. I took no offense with your comments. I would
never be upset that someone is looking out for me. Removing the engine,
coils, ECU, handset, exhaust, etc would be labor intensive, as the coils are
mounted on the firewall, the wiring for the ignition and handset go all the
way from the firewall to the instrument panel in a narrow center console that
took hours to "snake" the wires through, (engine is in the rear, and panel is
in the front on a pusher) the handset is hard-mounted to the instrument
panel, and the engine is mounted with an aluminum plate sandwiched between the
oil pan and block, so removal would require reassembling the pan, shortening
the oil pickup tube so that I could install the pan without the 1/2" thick
aluminum spacer, my water pump has -16 AN fittings welded to it, so the dyno
tuner could not use radiator hoses, and a host of other tasks, which while not
impossible, are very time consuming to say the least. I would gladly pay
a lot of money for someone to do it on site. (mobile tuners).
As far as the fuel tank
debris is concerned, that is a well known fact amongst the canard
community. I am fortunate that my fuel strakes are different from other
fiberglass canards, in that they are already completely formed by the factory,
(a top and bottom), with fuel tank openings already installed prior to
installing them, so there is no drilling, sanding or fabricating, just
glassing the top and bottom together on the fuselage, and that is all done on
the outside of the fuel tanks. I still, however check my fuel filter screen,
just in case. So far, nothing.
Thanks again for all of
your valued input and suggestions. I have not totally given up on the
MicroTech....just considering my alternatives, and as they say, it costs
nothing to do your homework. Yes, I was lucky to get the aircraft (and
myself) safely back to Earth in one piece. I don't care to repeat that
excercise any time soon....I am going to pull the spark plugs today and take a
good look at them, and start my trouble shooting expedition. Take care,
and thanks again for your valued input. Hey....if you'd like a mini
vacation in the states, we'd be happy to put you up and buy you steak and
lobster....
Paul, I'm so
confused, Conner
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