Ed Anderson wrote:

Yvon,
    What is the source of your injector trigger signal?  I have a friend

who

has a Holley throttle body injector on a 13B.  He lost the lead ignition
module which also provided the signal for his throttle body fuel

injector.

As a backup plan, he decided to wire a switch so that he could switch

from

the leading igntion module to the trailing tachometer output as an
alternative trigger source.  He finds that it will start on the signal

from

either module, however, if he switches it during engine run the engine

dies.

I had the same arrangement on my HALTECH system (before I got Tracy

Crook's

EC2) and it worked just fine.  So I was wondering what set up you had?

Ed Anderson

Allo!
First I must say that my 13B is a 1986 model, but my ignition is a Mazda
1985 electronic distributor and coils. That is two separate coils, one for
the leading circuit and one for the trailing circuit.
Inspired by the aircraft engine ignition system I separated the two Mazda
ignitions and I control the leading and trailing independantly through two
separate switches. The engine will run on either one or on both. There is a
loss of power when running on the trailing only, but I am confident that I
would maintain controlled flight to the nearest landing site.
 The Holley FIS is controlled by the electronic control unit which gets
signals from the (-) side of the ignition coil. (See attached diagram)
When I installed my Holley FIS I wanted the retain my two separate ignition
systems so I added a two pole switch and wires to the (-) side of both
ignition coils. The Holley electronic control unit works equally well on
either coil output. I have never tried it on both and cannot do it with my
present circuits. Since it works to my satisfaction as is I do not tamper
with it.
Start up goes like this:
Energize leading ignition
Energize trailing ignition
Energize Holley electronic control unit with trailing ignition coil signal
(leading coil signal is in reserve)
Energize fuel pump(s)
Energize main switch (the fuel pump and injectors will run briefly and
pressurize the system to 13-14 psi)
Set throttle
Engage starter (I have tried hand starting and it will start  but I find it
inconvenient and dangerous)
Usually engine starts right away.
If I am not clear, well, ask away.
Yvon Cournoyer.

 
The AirCraft Rotary Engine NewsLetter.              Powered by Linux.
ACRE NL web site. Copyright 1998-2002 All world wide rights reserved.
http://home.earthlink.net/~rotaryeng/            http://www.linux.org