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  1. C5Engineer added a post in a topic HAPPY BIRTHDAY AKFLYERBOB   

    Leni where has bob been hiding?
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  2. EDMO added a post in a topic 582 charging   

    yes - Love the info - Now, got to get Dusty some useful info....for ALL the 2-strokers!
    We got the Key West info - but no info on his overvoltage - unless it is just, not having the Key West?
    EDMO
    BTW:  I am parting out my 532 - If anyone needs starter / stator thingy, etc.  PM me.  Exhausts, Carbs, fuel pump, A-drive and adapter plate are already sold.  Still got the engine with thingys on it....Sold my boat, so don't need an anchor! 
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  3. EDMO added a topic in Hardcore Avidfoxflyers   

    HAPPY BIRTHDAY AKFLYERBOB
    Hope you have a happy Day - not going to leave you out!
    Good Flying,
    EDMO
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  4. C5Engineer added a post in a topic 582 charging   

    Great discussion guys! Love this forum and our members taking the time to share knowledge.
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  5. C5Engineer added a post in a topic Overhaul time!   

    Not really a stock rebuild. Cylinders had no damage and no measurable wear. They were honed for the first time and Pistons replaced with WSM ceramic coated Pistons. They are .0015 bigger than OEM. He said my rod bearings still had the copper coating on them and they looked great. Of course rods and bearings were replaced. Rick uses an upgraded double slotted Rod. Nothing abnormal was found in the bottom end either. No real explanation for the piston damage. Hoping it makes some better power when it comes back.

    I ordered a bunch of parts today. Replacing my fuel pump and pulse line and totally rebuilding my carbs. Order your Bing 54 rebuild kits from Bear Perkins. His price is $13 less than CPS. They are still stupid expensive.

    I pulled a wheel today and measured my axles do I can get going on the new gear. I also made a piece and riveted it onto my firewall to patch the hole where my old cooling line went to the side radiator. Slow going but I am making progress. It'll come back together quick once I have all the plumbing done and the engine back. I think I will cover the hole in the cowling with cardboard and fly it before I go totally past the point of no return and glass it in.
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  6. C5Engineer added a post in a topic Overhaul time!   



  7. EDMO added a post in a topic 582 charging   

    Chris,
         Thank you for all the writing and the most informative answers I have ever gotten.
    Question:  I also have a 40 amp Nippon alternator internal regulator - what wire do I put the circuit breaker on?  Hot-Output wire?
    I thought that once an alternator was energized, then until engine shutdown, it was self-energizing to the field  unlike the old generators.
         Unfortunately, we have now lost track of Dusty's question of 16 volts (?) from his 2-banger thingy! 
    Sorry Dusty, but this was the best chance for me to ask my question too.
    EDMO
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  8. akflyer added a post in a topic Overhaul time!   

    Jim, yours has the classic "4 corners" cold seize marks.  Joeys is only scuffed on the intake side and that is what makes it a head scratcher for me. 
     
    A lean burn down is normally on the exhaust side and starts with the lip of the piston melting then progresses from there. 
     

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  9. Guest added a post in a topic 582 charging   

    I'm writing too much and saying contradictory things when I re-read what I wrote. First I said automotive alternators do not have overvoltage protection when in-fact they do. What they do not have is catastrophic regulator failure protection. For the point I was originally trying to make it doesn't make any difference, but when we really dive into the details I should have been more exact. I think I'll give it a break for a while! )
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  10. Guest added a post in a topic 582 charging   

    Yes automotive alternators with internal regulators do have overvoltage protection...built in. And it works perfectly almost all the time which is why they are so reliable. I mean have you ever even heard of a modern automotive alternator failing in a runnaway condition? I havent. The problem is that the internal regulator over-voltage protection scheme still relies on the transistor I described above to cut the field voltage. If that transistor fails in a short, the alternator will run away with no way to turn it off. That's the difference between a true aviation specific alternator which is POSITIVELY controlled by the pilot via a switch and an automotive alternator with internal regulator.
     
    I worried about this on My Magnum which has a internally regulated automotive Nippon Denso alternator sold as an experimental aircraft alternator. I ended up putting a 40 amp button type circuit breaker (one of those you can pull to disconnect) in the pannel in easy reach. I figured if the alternator ran away, it might blow up some electronics in my plane (strobes, radio, transponder), but that i would figure out something was going wrong pretty quickly, look at the voltmeter and pull that breaker before more serious shit would happen like a fire or something. That was the compromise I struck with myself. Everyone has their own risk tolerance and what measures they want to incorporate to control risk. I figured in reality it was never going to fail, and if it did i could get it figured out quick enough so at most some electronics might get ruined, but that i would figure it out quickly enough to positively disconnect it from the system.
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  11. Guest added a post in a topic Overhaul time!   

    Yeah could have been cold seizure too....like Jim thinks happened to his. probably more likely. No matter what, the end game is the same (unless a hole gets burned in the top of the piston). Small amount of aluminium deposited on cylinder wall starts the process of more rapid deterioration.
     
    Excellant discussion! Very cool information to add to knowledge base (except for the money to get the engines overhauled or if someone gets hurt).
     
    Who is using TCw3 and who is using API TC?
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  12. KFfan added a post in a topic 582 charging   

    Ed
    Trying to be helpful
    I think automotive alternators have internal regulators and attendent overvoltage protection.
     
    This link is to a external overvoltage protection device.
    http://www.bandc.biz/over-voltageprotectionmodule.aspx
     
    I muddled through an extensive old post discussion on the RVairforce about this same subject. Unless you are a EE you may have difficulty understanding it. I sure got lost...
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  13. Guest added a post in a topic 582 charging   

    Oh...Certificated aircraft incorporate external regulators similar to #2 above, except the alternator and regulator are designed ground up specifically to be able to positively disconnect field voltage from the alternator.
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  14. Guest added a post in a topic 582 charging   

    Hi Ed,
    Your car doesn't have overvoltage protection because the regulators built into automotive alternators are so reliable that failures are virtually unheard of.
     
    Still, there is a lot of debate in some circles about the value of overvoltage protection in modern alternators used for experimental aircraft. Bottom line is there is usually a transistor in emitter follower configuration that regulates field current in most alternators. If this transistor fails (like I said, virtually unheard of) it would apply full field voltage to the alternator creating a serious runaway overvoltage condition that cannot be "turned off".
     
    In a car or airplane it would be an expensive proposition to fix all of the electronics that will blow up. In an airplane of course the potential consequences are worse because you are in the air.
     
    That said there are several approaches people take when using automotive internal regulator alternators in aircraft.
     
    1) do nothing and run the automotive type alternator as is which is what I think most people do.
    2) disable the internal regulator and install a custom aviation specific external regulator with circuitry that allows you to truly disconnect the field voltage with an ALT switch on the inst pannel.
    3) Install a Zener crowbar type circuit that blows a breaker which in turn incorporates a relay to disconnect the runnaway alternator output from the electrical system.
     
    Now what was it you were asking? )
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  15. Av8r3400 added a post in a topic Overhaul time!   

    Is this just a stock rebuild?

    Did he bore the cylinder or replace?

    If bore, had this been bored before?

    are the Pistons the same size?
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  16. C5Engineer added a post in a topic Overhaul time!   

    Heard back from Rick today. My engine is back together and almost ready to test run. He said the crank and rods looked perfect and didn't see anything else of concern. The day my engine lost power was no different than any other day as far as warm up goes. He didn't have any explanation to the piston. He's going to send them back with the engine so I can look into it further.
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  17. EDMO added a post in a topic 582 charging   

    Dusty was talking about overvoltage on 2-stroke, I think.
    I was asking about overvoltage protector for big alternators on certified engines and car engines.
    If my car doesn't have one, then why does my plane need one?  And, what kind is best?
    EDMO
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  18. 1avidflyer added a post in a topic Overhaul time!   

    Here are a couple of pistons I took out of a 582 that seemed to run fine.  It had an engine out before I bought the plane, shortly after take off, and the guy was able to land straight ahead on what was left of the runway.  Engine started up afterwards, and seemed to run ok.  He didn't have a thermostat in the engine, and it was about 45 degrees F.  I figure it was a cold seizure.  Had both cylinders bored to the next larger size and new pistons installed as there were some scratches in the cylinders.  Jim Chuk 
     
    PS,  just looking at the pictures, I think this is the same piston, not two different ones. 




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  19. Guest added a post in a topic 582 charging   

    What engine? Are we talking full on car / airplane type alternator or two stroke lighting coil? Most two stroke lighting coils have a hard time generating enough power to overvoltage anything. I am a fan of key west regulators for two stroke lighting coils. They are very nicely made and to my knowledge a pass regulator that doesn't need a load to regulate properly. However, the standard rotax shunt regulator works great too as long as there is a 1A or so load on it all the time, like position lights or something. If you are talking a full on alternator setup it is easy to understand how it could overvoltage if the field coil is fully energized by a failed regulator.
     
    Chris
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  20. Guest added a post in a topic Overhaul time!   

    Curious, what exactly happened leading up to the engine out?
     
    One of the most common failures is for an engine to seize momentarily because the piston expands faster than cylinder due to a lean condition and compromised lubrication. A partial throttle decent maybe. When piston cools everything runs perfectly like nothing ever happened....and this can happen so quickly that you might not even realize what happened, except a very small amount of aluminium is scraped on to a cylinder wall. The engine may run perfectly for hours, days or weeks after that. But...that small amount of aluminium on the cylinder rubbing against the piston just gets worse and worse until it self destructs.
     
    I'm only throwing this out as a possibility.
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  21. EDMO added a post in a topic 582 charging   

    I guess it just don't work to make funny statements when asking serious questions.
    There are no serious answers!
    EDMO
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  22. KFfan added a post in a topic 582 charging   

    I'm sure if you ever saw a rectalfire you would recognize it and be able to tell the difference...
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  23. KFfan added a post in a topic 2nd Annual RedHills Memorial Day Fly-In pics   

    Great, and inovative, video!
    Thanks!!
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  24. High Country added a post in a topic Are doors required for AW inspection   

    I would confirm this with the specific DAR that you are going to use but it shouldn't be a problem as they are not required, unless you have your "Experimental" placarding on them as I do in which case you will have to do something else for the placarding. good luck on your inspection
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  25. LSaupe added a topic in Kitfox III   

    Are doors required for AW inspection
    Looks like my last item to finish will end up being the doors (need to modify them for the wide body kit mod.
     
    I know you can fly without doors on these birds.  If time becomes critical can you go through the AW inspection without doors installed?
     
     
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