Received-SPF: pass
 receiver=logan.com; client-ip=72.52.218.78; envelope-from=bob@bob-white.com
Date: Wed, 16 Jul 2008 19:20:08 -0600
From: Bob White <bob@bob-white.com>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: No Spark from Coils
Message-Id: <20080716192008.111d84c3.bob@bob-white.com>
In-Reply-To: <list-3028925@logan.com>
References: <list-3028925@logan.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit

I know of another builder who was having trouble with no spark.  He had
the test mode and it sparked quite well, but wouldn't spark when
cranking.  He got the engine running by adding a second battery with
jumper cables.  I haven't heard from him for a couple of months, so I'm
not sure of his status right now.  Another item to check - bus voltage
while cranking.

Bob W.


On Wed, 16 Jul 2008 15:14:10 -0400
"Tracy Crook" <tracy@rotaryaviation.com> wrote:

> Bob gave you good advice John.  Pin C should have about a 3 - 4 volt pulse
> on it though (when cranking or running).  27 volts sounds like measurement
> error.  There is no source of voltage that high in the system.
> 
> Do you have the diagnostic modes?  Try it if so.
> 
> Tracy (back from Colorado)
> 
> On Sat, Jul 12, 2008 at 12:12 AM, Bob White <bob@bob-white.com> wrote:
> 
> > Hi John,
> >
> > Pin A to engine ground is correct, pin B to EC2 ground is correct, +12V
> > on pin D is correct.  I'm not sure what you will read on pin C with a
> > voltmeter.  It should pulse from 0 to +12V, and you will need an
> > oscilloscope to see it properly.  What really concerns me is the 27
> > Volts.  The EC2 ground lead is connected to the EC2 ground stud, and
> > that should be connected to airframe ground near the EC2, so that
> > voltage should basically be zero.  I'm not sure why you would see
> > anything anywhere above the 12 to 14 volt bus voltage.
> >
> > My first suggestion would be to double check ground connections at the
> > EC2, and make sure there is a ground strap between the engine and
> > battery that will handle the starter currents.
> >
> > The minimum load on pins 20 and 21 is several K ohms, and shouldn't
> > cause any problems, but just to be sure, can you disconnect it
> > temporarily?
> >
> > Bob W.
> >
> >
> > On Fri, 11 Jul 2008 23:29:31 -0400
> > "John Downing" <downing.j@sbcglobal.net> wrote:
> >
> > > Bob W,  today I joined the non-start rotor club, I expected it not to
> > start after following the Saga of Buly and Chris.  We don't have any
> > ignition.  We checked the wires to the coils and , all coil plugs have
> > ground to block on pin A, ground to EC2 on pin B, voltage on Pin D.  On
> > cranking,  Pin C on the volt ohm meter on cranking shows 9 volts, dropping
> > to 7 volts which is a steady reading on not pulsing.  Pin B which is the
> > ground to the EC2, voltage rises to 27 volts.  What is the voltage that we
> > should be seeing on pins B and C and should C show a pushing voltage?  Is
> > the Tach interface that you sent me, which is connected to EC2 pins 20 and
> > 21 for leading coils having anything to do with the fact that the coils are
> > not firing.  JohnD
> > >
> >
> >
> > --
> > N93BD - Rotary Powered BD-4 - http://www.bob-white.com
> > 3.8 Hours Total Time and holding
> > Cables for your rotary installation - http://roblinstores.com/cables/
> >
> > --
> > Homepage:  http://www.flyrotary.com/
> > Archive and UnSub:
> > http://mail.lancaironline.net:81/lists/flyrotary/List.html
> >
> 


-- 
N93BD - Rotary Powered BD-4 - http://www.bob-white.com
3.8 Hours Total Time and holding
Cables for your rotary installation - http://roblinstores.com/cables/