Ahh.. Music to my ears John : )
And this brings up the subject of risk (rotary & otherwise)
that Al W. (and every other builder I know) is concerned with. I agree
with Al W. that getting to the major causes of failures is a (hell, THE) key
issue. That is why I have not spent much time on the crank angle sensor
single point failure question. I have never seen or heard of a confirmed
Mazda 13B CAS failure. Can it happen? Of course. I am in the
process of developing a dual CAS for the Renesis CAS but it is not a 'front
burner' project.
I'm reading between the lines of Al's posts but it seems that he is
emphasizing the importance of leaving the engine as un-touched as
possible. I once wrote an article for Light Plane World (EAA's ultralight
magazine back in the late 80's) and advocated the same thing after noting that
many Rotax failures occurred soon after the owner opened up the engine for
maintenance. Decarboning the piston ring grooves was important but many
builders were causing more problems than they fixed when they went inside so I
recommended some products and procedures that would do the job without opening
the engine.
That was the basic gist anyway but I eventually decided this
was not a reasonable approach for builders who planned on installing an
alternative engine in 200 mph category airplanes. There were simply far
too many areas where things could go wrong in this process. The root cause
of the problems had to be identified. One of the names I gave to the
cause is a term I recently used on this list - Shopcraft (or lack
of). This referred to the ability to identify the quality or
suitability of virtually everything that goes into the plane. Yes, I know
this is a generality of the highest order but if we are to get to the root
cause of failures in the field of alternative aircraft engines, this level of
abstraction is required.
It has been suggested that a collection of 'best practices' might
be a solution. This may help but it is not a solution. There is
an unlimited number of potential problem areas so a list of them could never be
compiled. So, how do you learn to recognize what is or is not a
'good thing'? I'm getting so frustrated just trying to describe the
problem that there may not be a solution, at least not one that can
be spelled out in something like an email message. Damn,
now I can't even criticize Al W. for not spelling it out.
The best I can do for now is to emphasize two things. Pay
attention to every detail and admit to yourself when you don't have the ability
to execute something well. Another version of these rules was
given to me long ago:
1. Rules are for those who are not smart enough to make up
their own. (Author unknown)
2. A man's got to know his own limitations. (Dirty
Harry)
3. Always follow BOTH rules 1 & 2.
Small details like the problem of soldering thermocouple wire to a
connector that Al Gietzen mentioned can be critically important. He
was able to recognize the problem (he made a lousy solder joint) and devise a
solution (acid flux) even though it violated one of the cardinal rules of
electrical wiring. He recognized that too and took the steps necessary to
achieve satisfactory results (knowing when to make up his own
rules).
Out of time, I'll stop blathering now.
Tracy
Subject: [FlyRotary] EC2 problems - solved
Tracy and
others.
Following more than 12 months of battling with EC2 issues
I'm pretty sure it's Eureka day!
After
rewiring and testing for almost 4 weeks I plugged the EC2 in last night, and
got exactly the same symptoms as before. NOP flashing indicating no
communication. I took the EC2 to Buly's plane and tried it in his
installation. Same NOP, so I was thinking I'd fried it again. Before sending
it back yet again I decided to install it my plane one more time and see if
there was a spark.
To my
amazement it worked. No NOP, and I could bring up the EC2 data. The only thing
that changed overnight was that I moved the cable to unplug it. I climbed in
the back and found that I could make the NOP flash, or stop flashing, by
moving the cable. I haven't taken the connector apart yet, but I'm
expecting to find a broken wire inside the insulation, probably near a solder
joint at the pin. Whenever I bent the connector outward for testing it
made contact. When I bent it back to plug it in, contact was lost.
Bingo!
John
Just guessing, but maybe the new EC2
can't communicate with a pre-autotune EM2 like Buly's.
???