 
In
our Installation and Operating Guide, we try to keep necessary and helpful
information from becoming "too much" information. As a
result, there are undocumented features and techniques left out of the
manual. Some of these items can be very helpful - when and if
needed.
On this page, we will indulge a little extra
"print" to expand on some of these items. Not all comments
will apply to all installations, to all ignitions, or to all firmware
versions. This section assumes you already have a basic working
knowledge of the system. We also DO NOT list the many safety
precautions/procedures/standards that may be required - proceed with
caution. Tips and tricks will be added on an ongoing basis so keep
watching. If you have a tip - send it to us and we can pass it
along. Don't need to "BLOW"
- Alternate for "blowing" in the MAP
tube (Quick-Set timing): The manual calls for
blowing in the MAP tube (0.5" psi for one second) for each of the
(two) Quick-Set timing commands. If disconnecting the MAP tube
is inconvenient, you can pinch (or fold) the MAP tube approximately
1" away from the nipple at the ignition, and then pinch the
trapped air chamber to simulate the "blow". This can
make our simple timing routine - even simpler.
Sight-line to the ignition LED
- A shiny wrench held at the proper angle can
help if you are needing to wiggle the prop, and at the same time, look
for the green or red LED on the back of the ignition. Some
have installed reflective/polished metal tape (or polish a strategic
spot on the firewall itself) to accomplish the same thing. Fiber
optic tube can provide a flexible line of sight directly to the
cockpit, or a short piece can re-orient the LED beam so its visible
thru the oil filler door. Also, see below "Alternate TDC
signal" (first bullet) to see how you can add an audible signal
to supplement the "GREEN" LED function.
Alternate TDC signal
- Audible
timing reference and a way to check tach output
- In most "recent" versions of the
firmware, the ignition will signal TDC (concurrent with the green LED)
by sending continuous tach voltage to the tach terminal (#6 on the
green plug). This has two nifty uses.
- You can connect a small piezo buzzer to
terminal #6 (tach) and to terminal #1 (ground) and mount a buzzer
at a remote location (by the prop or in the cockpit). This
provides a convenient (audible) TDC signal (green LED equivalent)
without a sightline to the back of the ignition. You can
check ignition timing without removing the cowl - you can
"hear" the TDC (green LED) signal. The LED
function will be unchanged (still works).
- The other use is testing your tach
output. Previously, confirming our tach circuit, or
measuring the tach output voltage (5 volt vs. 12 volt) required an oscilloscope.
Now, with the ignition 1) in setup mode and 2) positioned at TDC
(confirmed by a continuous green LED), you can check the tach
circuit output with a simple volt meter. Note: You may need
to disconnect other tach leads from the plug to make sure you are
testing the ignition output (alone), and eliminate interference
from the tach wire or the tach instrument. If your firmware
version doesn't have this feature, it will register nothing (no
voltage).
Reminder - We have a Troubleshooting
Tips guide on our Downloads page.
9 volt Battery Prop-Starting
You have seen our booth demonstration at
airs shows where we power the ignition with a 9-volt battery in order to
show:
- How Quick-Set timing (blow-in-the-tube)
works.
- How little current the ignition draws.
The ignition will make sparks powered only by the small
battery. We explain that emergency prop-starting could be
accomplished in the same way.
Earlier this year a customer relayed a story of
how this routine was put to the test. His group had flown to an
out of the way spot (small airport) for an overnighter. In the
morning, they discovered one of the planes had left the master switch on
and totally drained the battery. Remembering our demonstration,
they scrounged a 9 volt battery, wired it in, and prop started the
engine.
Bottom Line - If you're going to keep a flashlight in your
flight-kit
anyway, you might as well get one that uses 9-volt batteries. Remember, if starting this way you'll want to make
sure the 9-volt supply is isolated and powering the ignition ONLY (not
back feeding the rest of the buss). You might keep the master
switch OFF, or pull the ignition breakers, or make certain everything
else on
the buss is OFF while you are prop starting the engine. Once the
engine is running, give it some time to charge the battery so you'll
have power from the craft if needed (you still want the ignition to have two
sources of electrical power).
Low Mass Props:
Kick-Back Precaution
Lightweight low mass props, by their nature,
have less flywheel effect on the engine. This allows the engine to
decelerate much quicker as the starter motor pulls against each
compression stroke, and as the engine approaches TDC - where the plugs
fire for startup. Under the right conditions, the combination of
low mass prop, weak or undersized battery, corroded terminals, cold
engine, long cable runs, tired starter (or any combination) can cause
the engine to come to a (virtual) stop by the time it reaches TDC. At
this point there is a 50/50 chance the engine will move forward or
backward (a so-called kick-back) when the plugs fire. While the
ignition may be performing as designed, the results are the same.
Fortunately, there is an easy defense.
Simply re-time the ignition with the engine
parked two or three degrees "AFTER" TDC (instead of
"AT" TDC as you normally would). AFTER TDC means
(from the TDC position) rotate the prop in the normal direction of
travel to your revised target timing mark. Note: This will also
slightly retard the operating advance range, but this small amount is
not likely to be noticeable for most flyers. If desired, the shift can
be nulled with the EICAD interface.
Caution on Ground Charging
Some styles of ground (110 volt)
chargers will hammer the battery with pulses as part of their
normal charge cycle. Such hammering is not a typical
buss state and can cause problems for the ignition if it is
powered ON during such a charge. KEEP IGNITIONS POWERED
OFF WHILE (GROUND) CHARGING.
Caution for PM Alternators and/or Small Buss
Batteries
We have learned that certain types of permanent
magnet alternators, alone or in conjunction with small light-weight buss
batteries, can induce significant voltage spikes to the electrical
buss. These spikes are capable of overdriving (heating to the point
of failure) the power regulation section of our ignition. E-MAG
customers need to verify the electrical buss supplying power to the
ignitions is properly regulated and filtered. If using a permanent
magnet ("PM") alternator, a properly designed crowbar circuit
should be considered MANDATORY. Customers should also be aware that
many of the new non-traditional (non lead-acid) batteries (gel-cell,
lithium-ion, lithium-iron phosphate, etc) frequently have different
charging profiles. Anytime a battery is unable to absorb/buffer
output from the alternator, the excess will likely go out to all the appliances
on the buss, including our ignition.
Tach Signal mod for Vision
Microsystems
Credit to customer Howard Kanner for working out
a tach signal solution for Vision Microsystems engine monitor. . .
. "It took me a couple of months to settle on a solution
for tach signal, but my tach is stable now in the many flights since my
last test iteration. I’ve settled on a 250 ohm resistor across the tach
input to the VMS box." Thanks again Howard.
Annual (or 100 hr)
Inspections (which ever comes first)
E-MAGs require very little maintenance. The
system has very few mechanical "wear" parts. Even so,
there are a few items you can do at annual to check the condition of the
ignition - none of which require disassembly of the unit
itself. The Installation and Operating Guide Maintenance section
references the following areas you can inspect.
1.
Check E-MAG web site for most recent Service Notes and verify equipment is
current.
2.
Ignitions come with a (one-time trigger) thermal sticker that will trip
(turn from
light
ash color to gray or gray/black) if case temperatures exceed 200 degrees
(F).
If tripped, review blast cooling and/or other ventilation issues that
affect
ignition
cooling. Keep ignition temperatures below 200 degrees.
3.
Ohm check plug wires (see “Ohm Check” above), and examine spark plugs
for
signs of unusual wear or build-up. Gap plugs per instructions above.
Replace
auto style plugs with new ones after 100 to 125 hours. When reinstalling
auto
style plugs with auto plug adapters, review plug/adapter
installation
guidelines in the manual.
4.
Remove ignition and examine shaft and drive gear condition. Note: Ignition
disassembly is
not
necessary (and if done may void your warranty). Look for excessive play
(lateral
and axial). Shaft rotation should be free, with no catching, flat spots,
or
grinding. The shaft on “P” models (with internal alternator) will have
a
push-pull
rippling effect as the shaft turns and the permanent magnets pass
the
rotor poles. This is normal and expected. If a P model ignition does not
have
this magnetic ripple, the unit requires additional (shop) service.
5.
Examine control plug and coil plug connections. Verify there are no stray
wire
strands
or loose wires. Verify all control wires use the Adel clamp strain relief.
6.
Reinstall the ignition, re-time, and verify proper operation. For P
models, re-verify minimum operating speeds
when
running on internal power (see Minimum Operating Speed test in the
manual.)
More to come . . . . keep watching.
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Setting New Standards 
