(Section 2.2 "TRIGGER COILS" is only applicable to PLASMA I CDI TRIGGER COIL SYSTEMS purchased before 2001.  Trigger coil systems can be identified by a "-T" after the serial number.)
 

2.2 TRIGGER COILS

Lycoming Engines

LSE provides trigger mounting plates ready to install to your Lycoming engine.

There are 5 different plates available depending on your engine model and size of flywheel used. The older generator flywheel has a pulley measuring 6.5 inches on the inside. It requires a 7° skewed mounting bracket to mount the coils closer to the case. This 7° offset must be considered when the trigger bolts are installed. Refer to drawings 3a, 3b, or 3c.

The trigger coil plates also come in two different sizes of bolt patterns:

1) The 0-235, 0-290 and early 0-320 cases use the smaller pattern.

2) Later 0-320s and 0-360 cases use the larger bracket.

Some very old engines do not have any bosses around the crankshaft main seal. In this case the trigger coil plate needs to be mounted from fabricated aluminum angles under the through bolts of the case.

TRIGGER COILS, LYCOMING ENGINES

Some later engines come from the factory with seal retainer plates installed. Here the LSE trigger plates are a direct replacement and will also act as a seal retainer.

4-CYLINDER BRACKET (FIGURE 3A OR 3B):

The alignment tabs (not available on 6 cylinder trigger coil plates) assure concentricity to the crankshaft and the "V" notch aligns with the seam in the case. After tapping the threads, trial-fit the bracket one more time, making sure that the alignment tabs contact the crankshaft and the "V" aligns with the seam of the case when the bolts are tightened.

Now break off the three inner centering tabs first and then the two outer control tabs. This sequence is important as you might damage your crankshaft if you fail to break all three centering tabs off. The outward pointing control tabs allow easy verification of the removal of the centering tabs. DO NOT REMOVE THE OUTER CONTROL TABS UNLESS ALL THREE CENTERING TABS ARE REMOVED.

Don't forget to set the clearance between trigger coils and bolts. There are 4 places to check on 4 cylinder engines and 6 places on 6 cylinder engines.

6-CYLINDER PLATE (FIGURE 3C):

Use an LSE supplied spacer, or a dial indicator for concentric installation of the mounting plate. Clock the mounting plate per drawing 3C.

CONTINENTAL ENGINES

LSE provides brackets for various Continental engines from 0-200 to TIO 550.

On the 6 cylinder engines a trigger bolt holder is installed under two of the propeller studs. Be sure the trigger coils are mounted concentrically around the crankshaft so the bolt clearance is equal to all trigger coils. Position the trigger coil plate and the trigger bolts such that the second bolt is adjacent to the core of one of the trigger coils when the crankshaft is at TDC.

The first bolt (in the direction of engine rotation) should then be adjacent to the core of the same trigger coil when the crankshaft is at 45° BTDC for engines with compression ratios of up to 8.5:1 and at 40° on higher compression engines. A small metal rectangle is the reference (core) on the trigger coils.

All 6 cylinder engines need 3 ignition pulses per revolution for the processor. thus the 120 degree spacing of the trigger coils on their mounting plate.

This plate is mounted to the engine case on 4 predrilled holes. The plate must be mounted concentrically to the crankshaft so that its ID fits around the crankshaft. Rest the plate against the shaft and fasten it to the case using existing 10/32 holes in the case. Mark the exact position of the plate on the case, and remove the plate to provide ¼" clearance from the shaft by enlarging the ID of the plate . If the plate overlaps onto the seal it will act as a seal retainer.

Install the trigger coil plate with the trigger coils and their spacers mounted facing forward. The trigger bolt bracket is mounted as shown under the top two nuts that fasten the propeller hub to the crank shaft when the crank shaft is in the TDC position.

The top trigger coil fires cylinder 1 and 2. If the crank is at TDC a trigger bolt must be installed adjacent to the center of that trigger coil. Drill and tap the bracket for the trigger bolts such that they align with the center of the coils. Rotate the crank backwards to 37 or 38 degrees BTDC and the other boss on the trigger bolt bracket should align with the same coil. Install the second trigger bolt in alignment with the trigger coil center.

 Install trigger coils following the procedures outlined below.

TRIGGER COIL INSTALLATION PROCEDURES:

Mount the trigger plate to your engine per drawing 3a, 3b, or 3c. Be sure to remove the alignment tabs (first, inner centering tabs then outer control tabs, in that order) from the plates before you run your engine.

The trigger is a modified 10-32 AN bolt. It must protrude from the surface a minimum of 0.7" when locked by the jam nut to avoid false triggering at high RPM. The threads should be engaged 0.2" or more. Adjust the clearance between both bolts and all trigger coils to .025" ±.010".

If a trigger coil bracket is not available from LSE you may need to build your own. On 4 cylinder engines two trigger coils must be mounted firmly to the crank case, concentrically around the crankshaft such that a 10-32 bolt mounted to the crankshaft, flywheel, extension or spinner moves past the face of each trigger coil with a clearance of .025" + .010". On 6 cylinder engines three coils are mounted with 120° spacing.

On all engines, the second bolt that moves past the trigger coil must be mounted across from the center of the coil when the crankshaft is at TDC. The first bolt is installed 40° or 45° ahead depending on compression ratio of your engine.

Refer to the LSE drawings 3a, 3b, or 3c for detailed information.  

2.3 HALL EFFECT SENSOR MODULE INSTALLATION

To install the accessory case driven Hall Effect Sensor Module, please follow the following instructions:  

Install a magneto drive gear from a non-impulse magneto onto the shaft of the sensor module using the same woodruff key as well as the LSE supplied washer and locknut.

Fasten the gear in a soft jaw vise and tighten the nut to 30 lbs/ft ensuring that the washer is centered on the shaft.

The module can be installed on either mag pad using standard clamps.  Install all system wiring except the BNC connectors on the ignition module.

Remove all sparkplugs from cylinders and turn the crankshaft to TDC #1 and #2 cylinders using the factory timing marks.

Turn electrical power on, and rotate the sensor module in the accessory case counter-clockwise until the green light on the module case turns on and then off again.  Maintaining its position, fasten the case with toe clamps commonly used with Slick Magnetos.

Light Speed Engineering highly recommends that you check ignition timing using a strobe light, automotive style, both on your new ignition and, should you still have one, on the magneto.  The magneto timing should be set to the manufacturers specs.

Use a conventional "clip-on" inductive timing light to verify the timing accuracy and range.  Only use a simple strobe light that does not have a potentiometer or display.  The Plasma CDI’s wastespark ignition will give erroneous readings on these strobe lights. Always use only the timing marks on the engine side of the flywheel. The reference for this is the split line of the case.  See section 3.2 for detailed instructions.

The timing is now correctly set for those engines normally timed at 25º BTDC (usually standard compression ratio).  During start, the system will fire at TDC for standard compression engines with ratios less than 8.7:1.  At idle the strobe light should indicate 21º + 2º when the manifold pressure hose is disconnected and 40º + 2º when connected.    

If you are using a compression ratio of 8.7:1 or higher, the timing must be retarded another 5º.  In this case, position the crankshaft to 5º after TDC and use the procedure outlined above. During high compression engine start, the system will now fire at 5º ATDC.  The idle strobe light readings should be 16º + 2º when the manifold pressure hose is disconnected and 35º + 2º when connected.  These values are for sea level conditions.  Slightly higher values apply at altitudes.

Note that these numbers are for sea level.  You can add 1 degree for each 1,000 ft of density altitude.  The low number (MP hose disconnected) is the most important.

The Hall Effect Sensor module should be removed every 50 hours and inspected for gear, bearing, and seal wear.  After first inspection, inspect as necessary or at least every 100 hours by removing the cover plate and checking for bearing and seal wear.

 2.4 DIRECT CRANK SENSOR INSTALLATION

The crank sensor circuit board has two completely independent triggering systems if it is used for dual PLASMA CDI applications.   On single installations only the outer set of sensors and associated wiring is installed.

Remove the flywheel to install the magnets and the crank sensor assembly.  The outer trigger magnets are installed in the flywheel on a 4.000" radius.  The inner trigger magnets, used for a second system, are installed on a 3.840" radius (refer to the picture below).  You may wish to send your flywheel to LSE for installation of the magnets and the timing marks; cost is $50 plus shipping; plan on 1 day plus shipping time.

Please refer to the attached pictures and those on the Crank Sensor page of the web site (www.LightSpeedEngineering.com) to mount the sensor plate to your crankcase and integrate the trigger magnets into your flywheel. Use a number 32 drill, 1/8” deep so that the magnets can be pressed in flush with the surface. Use Loctite and stake around them. Two or four magnets are included. Single systems require only two magnets on the 4” radius. Looking into the pulley side of the flywheel, the left magnet position should always line up with the TDC indication under the starter ring gear. For the other magnet position, add 20 degrees to the recommended timing for your engine and install it on the same radius to the right of the first magnet. On engines that should have their magnetos timed at 25 degrees, the leading magnet should be installed at 45 deg BTDC and thereby 45 degrees to the right of the TDC magnet. Only the magnet's south pole can trigger the sensors.  This is the face marked with an X and therefore, should point to the sensor.  In other words, the X must be visible after installation.  If the X is not clearly visible,  use a compass to identify the correct polarity.

Large diameter alternator pulley required (8.5" ID).   

If you have seal retainer plates installed, remove them and use existing holes to mount the bracket.  You might have to adjust the holes in the bracket using a dremmel to make them align with the existing holes.  If the bosses are not drilled,  use the mounting plate as a drill template as follows.  

Align plate concentric to crankshaft by registering on centering tabs.  Visually align crankcase split line with the v notches between the top and bottom 2 holes of the mounting plate.  Mark the crankcase mounting locations through the existing holes in the bracket. If possible, use a #2 centering drill for a pilot hole.  Drill #6 (0.2040) x 5/8” deep.  Tap ¼-20.  For best results, use a 2-flute spiral point HSS tap with aluminum tapping fluid such as Tap-Magic.  Once the bracket is mounted to the crankcase, remove the three alignment tabs then remove the two control tabs.  This sequence allows you to later verify that the alignment tabs were removed. If the circuit board was removed for this operation, re-install it.  All screws holding the crank sensor circuit board to the mounting bracket must be secured with Loctite and the proper torque.  The 0 degree mark on the circuit board should now align with the split line in the crankcase when the screws are fastened in the center of their positing slot. 

Now that the sensor plate is installed, perform a simple operational check: disconnect all high tension leads from the ignition coils. With power to the system and all else connected, take any magnet and swipe it back and forth past each sensor (speed is important, > 2x per second). Every other pass should produce a loud spark at the coil. Only the south pole works. Check each sensor.

 
Lycoming external engine dimensions can vary significantly, so you need to verify the proper clearance between the sensor and the magnets installed in the flywheel surface. Two measurements need to be compared to determine the gap. 

 ·         First, measure the height from the inside of the flywheel where it touches the crankshaft flange to the surface that has the magnets installed.

 ·         Then measure from the face of the crankshaft flange back to the sensor face on the circuit board. This second dimension needs to be larger by .030”- .060”.  The clearance should fall within these parameters with the crankshaft pushed in and pulled out.

 Too little gap and a flexing crankshaft might touch the sensors. 
 Too much gap will not activate them.  

Adjust by adding washers to the circuit board spacers (adding clearance) or by adding washers underneath the bracket attachments (subtracting clearance).

** Note- Magneto removal:
When removing the magneto(s), be sure to remove the mag with its drive gear and pilot bearing. Install the mag hole cover plate provided by LSE in place of the magneto.  Use only liquid sealant and the magneto "toe clamps" to secure this plate.  Gaskets are not recommended as they may distort the cover plate.

  You may wish to send your flywheel to LSE for installation of the trigger magnets and timing marks; cost is $50 plus $10 for insured shipping; plan on 1 day plus shipping time.

2.5 IGNITION MODULE AND IGNITION COILS

The PLASMA CDI module should be mounted in the electrical compartment of the aircraft or on the cold side of the firewall. In certain cases mounting on the engine side of the firewall is permissible if the components and connectors are shielded from excessive heat and moisture.  In this situation, the module should be oriented such that the connectors are to the sides of the plane and a protective metal cover should be used to protect the module from water/engine cleaning materials.  Air must be allowed to flow between the bottom of the module and the mounting surface.  

Ignition coils are typically mounted on the top center of the engine.  They can also be mounted on the motor mount tubes using adell clamps or on the fire wall to a piece of angle aluminum.  Ignition coils should be mounted so that spark plug lead length will be kept to a minimum for maximum spark energy and minimum noise. It is important that each coil connects to opposing cylinders, i.e. one coil fires cylinders 1 and 2 and the other coil fires 3 and 4.

CAUTION!

BE CAREFUL NOT TO DRILL INTO ANY PRIMARY AIRCRAFT STRUCTURE WHILE MOUNTING YOUR PLASMA CDI SYSTEM.  THE BEST IGNITION SYSTEM IN THE WORLD WILL BE NO HELP IF YOUR MAIN SPAR FAILS.

WARNING! 

• WIRING CAN CAUSE ELECTRICAL SHOCKS WHEN IGNITION IS TURNED ON.

• DO NOT TOUCH ANY WIRES WHEN SYSTEM IS IN OPERATION.

• DISCONNECT BATTERY BEFORE INSTALLATION AND TESTING TO AVOID SHOCK.

2.6 ELECTRICAL REQUIREMENTS AND OPERATION  

Electrical System Requirements

All Plasma CDI systems can be used with 12 or 24 volt electrical systems.  Input voltages above 35 volts or reversed polarity will cause system damage.

For this reason it is mandatory that all aircraft using Plasma CD Ignitions are equipped with over-voltage protection in their alternator charging system(s).  Over-voltage is a requirement for certified aircraft.  Power connection must be directly to the battery terminals to avoid voltage spikes and electrical noise.  Aluminum should never be used as an electrical conductor for the Plasma CDI.  Use only the supplied aircraft quality stranded wire.

Minimum supply voltage for starting is 6.5 Volts.

Minimum operating voltage is 5.5 Volts.

Electrical Operating Instructions

No operational limits or special procedures are necessary during normal use.  You can either hand start your engine or use your electrical starter.  All Plasma CDI systems retard timing to TDC during start and advance timing optimally for all flight conditions based on manifold pressure and rpm.

• In case of a charging system failure, it is recommended that you land at the nearest safe airport and repair the system before further flight.
  

• If you are using Dual Plasma CD Ignition, you can turn one system off, together with all other electrical loads not essential for flight, to maximize your range with your remaining battery capacity.
  

• Dual Systems only: If you have installed an aux battery per the LSE supplied drawing, monitor your voltmeter and do not switch to the aux battery until the supply voltage of the main battery is below 6.5 Volts or the engine is not running smoothly.  After switching to the aux battery, your voltmeter will read the voltage remaining in your aux battery.
  

• Do not switch your main alternator breaker in flight to avoid potentially damaging voltage spikes.  This does not apply to the alternator field breaker.
  

** The above electrical operating information should be contained in the Aircraft Operating Manual. **

2.7 ELECTRICAL CONNECTIONS

HERE ARE SOME NOTES ON HOW THE SYSTEM IS WIRED UP:

The PLASMA CDI System includes a pre-assembled electrical harness/connector(s) with all essential wires ready to route between the triggering mechanism (Hall Effect Sensor, Direct Crank Sensor, or Trigger coils) and Plasma CD ignition module input connector.  The power wires in the harness remain un-terminated.  The input connector, output connector and manifold pressure input barb are located on one side of the Plasma CD module; BNC connectors for the primary ignition wires are located on the other side of the Plasma CD module. 

Pictured here: Primary ignition wire terminal connection to the ignition coil.

When connecting the power supply, route the positive lead to a 5A pull-able circuit breaker and then to the battery plus terminal, bypassing any electrical buss or master solenoid.  Refer to input connector diagram.

If a toggle switch is used as an on/off switch, it should be installed next to the circuit breaker.  If an aircraft key switch is used (some Plasma I systems and all Plasma II Plus and Plasma III systems only), do not use a toggle switch; instead, hook up the "P"-Lead from the output connector to your key switch.  Route the negative lead directly to the battery ground terminal (not airframe or ground buss) to avoid ignition noise.  The shield should not be connected.

For dual Plasma CDI Installations, an auxiliary battery is recommended.  Please click here for a wiring diagram.

Trim the power supply wires to length and connect them with quality crimp connectors or by soldering and heat shrink insulation.  Do not use any heat shrink on the black RG58 cable going to the ignition coils.  

Route the RG58 coax cables to the ignition coils.  Avoid their exposure to heat from cylinder heads or exhaust systems.  The primary ignition coil wires running from the Plasma CD Ignition module to the ignition coils can be routed together, however they should be kept separate from the ignition system input wires (harness).  There is no polarity on these, even though they might be labeled (+) and (-). Connect the center conductor to one ignition coil blade and the shield to the other blade using standard spade terminals.  Again, polarity at the coils does not matter.

The high tension leads supplied in the kit must be used with the PLASMA I and the PLASMA III CDI System since its spark energy is far too great to be used with any shielded aircraft leads or high resistance automotive wires.  The two high tension leads from each coil connect to spark plugs on opposite sides of the crankshaft.  One coil fires cylinders 1 and 2 and the other coil fires 3 and 4.

Connect the manifold pressure line to your ignition processor.  If you have a MP gauge, you can tee into that line.  A standard 1/8" ID MP Tygon tube is recommended.  Refer to your engine manual for manifold pressure pick-up.

LSE highly recommends that you check ignition timing using a strobe light, automotive style, both on your new ignition and, should you still have one, on the magneto.  The magneto timing should be set to the manufacturers specs.

Use a conventional "clip-on" inductive timing light to verify the timing accuracy and range.  Only use a simple strobe light that does not have a potentiometer or display.  The Plasma CDI’s wastespark ignition will give erroneous readings on these strobe lights. Always use only the timing marks on the engine side of the flywheel. The reference for this is the split line of the case.

You might want to build yourself a little pointer.
Mark the timing mark on the flywheel per the picture in the manual and again for the other channel(s): 180 degrees out for 4-cylinder or 120 and 240 degrees out for 6-cylinder.  You can then point the timing light from the cockpit in line with the center of the case at the marks. 

During start, the system will fire at TDC for standard compression engines with ratios less than 8.7:1.  At idle the strobe light should indicate 21º ± 2º when the manifold pressure hose is disconnected and 40º ± 2º when connected.

If you are using a compression ratio of 8.7:1 or higher, the timing must be retarded another 5º.  If you are using the Hall effect sensor module in place of the magneto, reposition it to show idle strobe light readings of 16º ± 2º when the manifold pressure hose is disconnected and 35º ± 2º when connected.

Note that these numbers are for sea level.  You can add 1 degree for each 1,000 ft of density altitude.  The low number (MP hose disconnected) is the most important.

Be aware that the indicated timing is dependent on the accuracy of the timing marks.

(1) Make a written note of the actual ignition timing as seen with the timing light for the most advanced position.

(2) Disconnect the manifold pressure vacuum hose. Verify retard to the correct values for your engine.

(3) Make a written note of the ignition timing for the most retarded position.

(4) Clip your timing light pickup to one of the ignition leads from the other coil. The timing light should illuminate the opposite set of timing marks on the prop-extension or flywheel in the same way.

(5) Check ignition timing with the vacuum hose connected, and with it disconnected, and compare the timing of each coil.

YOU ARE NOW READY TO GO FLYING!

HOWEVER, FIRST READ THE REMAINDER OF THIS MANUAL, SO THAT YOU HAVE A THOROUGH UNDERSTANDING OF YOUR LSE PLASMA CDI SYSTEM.

3.3 RUN UP TESTS

NOTE:

Due to the significantly higher performance of the LSE PLASMA CDI System, it cannot be compared to magnetos during run up in a conventional manner.

If fuel mixture setting is near optimum, there will be no detectable RPM drop when the mag is turned off and the engine runs on the PLASMA CDI alone.

A large RPM drop will be noticed when the electronic ignition is turned off.

No significant drop is noticed if two Plasma I or III systems, one Plasma I or III and one Plasma II Plus, or two Plasma II Plus systems are used and the interconnect feature is installed.

3.4 IN-FLIGHT TESTS

For normal operation always turn on both the magneto and electronic systems, even if the benefit of the magneto is not noticeable. If you have sensitive EGT information you may notice a lower EGT when both spark plugs are firing. Verify that all cylinder head temperatures are within normal limits. Too much timing advance might cause high CHT's.

Section 4 TROUBLESHOOTING

One of the first priorities in designing the LSE PLASMA CDI System was its reliability. State-of-the-art circuitry is used throughout combined with professional design. It is unlikely that failures will occur during normal operation.

This is unlike the conventional magneto systems where failure is predictable. Also, contrary to magneto or other distributor systems, there is no wear or other loss in performance over time. In short, it either works or does not.

IF SYSTEM FAILURE DOES OCCUR:

All components supplied with the PLASMA CD system have been carefully tested.  If any of these components are substituted, optimum performance cannot be guaranteed and such changes might affect the warranty.  If deviations from the instructions or supplied materials have been made, please correct those changes before contacting LSE with any problems.  

Consult the wiring diagram and assure proper connections of signal wires and power supply.

LSE recommends high tension lead replacement every 500 hours or every three years whichever comes first, independent of the ignition source.  

Trigger coil version: If one or more channels are not working, check the resistance at the connector for each trigger coil.  With an OHM meter verify that each trigger coil input to the 25 pin connector has 470 ohms + 50 ohms.

On Hall Sensor modules, remove the cover with its circuit board attached and inspect for bearing wear and oil contamination. If problems are visible, return the housing to LSE for inspection and overhaul.

With the spark plug leads removed from all coils and the 9 pin (Hall Effect Sensor module systems) connector in place and power on, rapidly move the south pole of a magnet past each Hall sensor. You should be able to generate a spark at the coils from each of the four sensors. Also, verify the gap between the sensors and the magnet to be 0.030" - 0.060". 

Using an ohm meter, the BNC cable should be open between the shield and the center conductor and about 1 ohm when it is connected to the coil. Measuring from each spade terminal to each output terminal of the coil should show an open circuit. Any conductivity here indicates a failed coil.

Verify the input wire harness (running from the triggering mechanism to the Plasma CD module) is routed with at least a 3” separation from the output wires (RG58 primary ignition wires running from the Plasma CD module to the ignition coils).  These wires must be routed through different holes in the firewall in order to maintain a 3” or greater separation.

4.1 STARTING PROBLEMS

If your battery can no longer crank your engine over, you can hand start your engine using proper safe procedures. The LSE PLASMA CDI System will provide an accurate spark every compression stroke on 4 or 6 cylinder engines as long as the battery has more than 8 Volts.

 For further information or questions concerning our products,
please e-mail lightspeedengineering.com or contact us at:

Light Speed Engineering™, LLC-