Mailing List flyrotary@lancaironline.net Message #46900
From: Ed Anderson <eanderson@carolina.rr.com>
Subject: Indication of Possible CSA problem - lesson Learned
Date: Sat, 4 Jul 2009 20:46:20 -0400
To: 'Rotary motors in aircraft' <flyrotary@lancaironline.net>

 

One thing, I would like to add to Joe’s excellent description of the troubleshooting it took to get things fixed up on his 20B.

 

Joe mentioned that the initial starting problem was attributed to a problem with the CAS wiring.  Well, I though some might be interested in how that was diagnosed.

 

Joe had used the simulator modes (both injector and coils) and they all worked fine.  You could hear the injectors chatting and could see the steady stream of sparks on the sparkplug.  So we knew he had the right connections to both injectors and the coils – the EC2 simulation mode told us that. 

But, it still wouldn’t start – wouldn’t even give a hint of rotor firing.  We could smell fuel, particularly after priming a few times, but there was no indication of combustion smells.

 

So Joe took a spare plug and hooked it up to one of the coils and proceeded to crank (injectors off) while I stood  and watched.  It was clear the spark plug was NOT firing during normal mode.  But, it did fire during simulation mode.

 

That was the clue that the EC2 was hooked up to the injector and coils correctly – as attested to by the simulation of both subsystems.  But, the fact that I could not hear injectors clicking and more certain the lack of any spark during normal mode made it fairly clear that the EC2 was not getting a good trigger signal from the CAS during normal start mode.  That led to the finding of a wiring error which rectification led to the successful starts.  So if your injectors are a clicking and spark plugs firing in simulation mode, but you still get no evidence of the engine firing – pull a plug wire or listen to the injectors while trying a normal start. 

 

Needless to say BE VERY CAREFUL – if checking injectors during a normal start mode  make certain the ignition is OFF.  Like wise if checking the ignition make certain the injectors are off – you would not want that thing to roar to life while you head is  a foot or so from the prop!!!

 

Also be aware IF you have fuel in your intake or the combustion chamber and your turn on the ignition simulator it may well cause the engine to fire and prop to rotate.  I’ve had that happen to me, the blade only move approx  30 -45 deg, but it still could have whacked you on the head hard enough to send you to medical.  So again be careful!!!

 

7 starts? Really Joe?   Must’ a been nice.

 

I’d also like to mention that Joe has a tangential muffler out  of fairly heavy gauge metal approx 6-8 “ diameter (as best I recall).  While the engine probably didn’t get above 1000 rpm or so while I was there, the tone was a deep throated muffled roar.  Sounded really nice, more like a deep throated V8 than a rotary – higher rpm will certainly make it louder, but it sure has a mellow sound at this stage.

 

Well that’s about all I wanted to add.

 

Ed

Ed Anderson

Rv-6A N494BW Rotary Powered

Matthews, NC

eanderson@carolina.rr.com

http://www.andersonee.com

http://www.dmack.net/mazda/index.html

http://www.flyrotary.com/

http://members.cox.net/rogersda/rotary/configs.htm#N494BW

http://www.rotaryaviation.com/Rotorhead%20Truth.htm

 

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