Hi Al,
 
The timing belt risk on your Subaru may be lower then you think, in my experience timing belt failures occur at engine start 9 times out of 10.  Most Japanese manufacturers recommend a replacement interval of about 70,000 miles, if the oil seals are replaced at the same time and the belt is re-tensioned after the first heat cycle you should be quite safe.  Ian
 
(Convinced that you are NOT flying the highest risk aircraft ever made ;-)

    -----Original Message-----
    From: Rotary motors in aircraft
    [mailto:flyrotary@lancaironline.net]On Behalf Of al p wick
    Sent: Monday, June 06, 2005 9:58 AM
    To: Rotary motors in aircraft
    Subject: [FlyRotary] Re: EC2 problems - solved / rotary risks

    When we are pursuing a problem like Johns, we are eager to find
    the cause. It's a great relief when we do. We say "Eureka!". We
    did it! We did it! This sense of relief is a root cause for
    failure. We are so eager to get the problem off our back, that we
    don't take the next step....
    Yes, I know you firmly believe this connector was the problem. But
    if you can force yourself to pretend it WASN'T, then you can do this:
    Is the cause logical? Like is that really the wire that causes
    that effect? If I remove that wire, does it have the same effect?
    What if I have two things causing the same thing? By pretending
    that really wasn't the cause, then you will do some more testing,
    looking around. Looking for similar connector issues, stuff like that.
         Now I have to admit, this really does sound like he found the
    cause. But I've seen this scenario so often. So you use the
    disciplines I suggest to reduce your risk. Logical cause? Can I
    make it recur?
    Repeat after me: "Al Wick is an idiot". "Al will jump to
    conclusions". If you believe that, then you start finding ways to
    prove your theory with facts instead of just accepting your first
    conclusion. My best asset is that I know I'm an idiot.
         Yeah, yeah, I know, you guys already knew I was.
         We had a perfect example of this on Cozy list couple weeks ago.
    Subaru engine slipped 2 teeth on timing belt. Would no longer
    start. Keith talked to expert and the guy said:"You know, the
    engine normally is never rotated backwards. But you've been
    pushing your new prop backwards recently (installing new prop). I
    think you relaxed the belt tensioner when going backwards and
    caused it to skip tooth." So Keith said" Yes, all of that's true.
    That has to be it."
         But then one of the guys looked into it, guess what? The direction
    the belt slipped is the opposite of that theory. That could not
    have caused it.
    The lesson? Prove all aspects of the theory are logical. Prove
    that all the various facts support the theory. Find a way to
    convert your theory to facts!
         Oh, by the way, if you look at my analysis of my engine
    risks....you will notice that timing belt is the highest risk item
    on this engine. So we have exposed another root cause for his
    problem. He didn't focus on the leading cause for all engine
    failures. When we reviewed some facts he had, we found conclusive
    evidence he had loose belt from day one! It was installed wrong.
         Regarding CAS risk. It's not just crank angle sensor that is the
    risk item. Going to redundancy with the CAS will dramatically
    reduce risk of all ECM causes. Like this connector risk. I'm not
    always proponent of redundancy, but with my limited info on this
    item, I SUSPECT it's significant, positive step.

    -al wick
    Artificial intelligence in cockpit, Cozy IV powered by stock
    Subaru 2.5
    N9032U 200+ hours on engine/airframe from Portland, Oregon
    Prop construct, Subaru install, Risk assessment, Glass panel
    design info:
    http://www.maddyhome.com/canardpages/pages/alwick/index.html
                   On Sun, 5 Jun 2005 21:44:00 -0400 "Tracy Crook" <lors01@msn.com
    <mailto:lors01@msn.com>> writes:

        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. ???