Your C. H. Capacitive Discharge Ignition system can be installed on most single or twin cylinder, two or four stroke engine.
THESE INSTRUCTIONS ARE IN THREE PARTS
- The battery
- Installing the ignition and engine in your plane
- Troubleshooting
- Timing with printable timing degree wheel link
These instructions are only for the ignition systems. If you ordered
an ignition with a T.C.S.A. or a Synchro spark, follow the instructions
that came with them for correct installation. .
SAFETY NOTE: The ignition can fire one time when the switch is turned off or on. Stay clear of the prop when turning the ignition off or on. If the engine would happen to be on compression, it could kick over.
BATTERY: Now that you have purchased the ign. module, you will
need a good 4.8 volt battery pack 800 MA or larger. MAKE SURE YOU HAVE
THE POLARITY CORRECT. Red wire is always positive and we always put
the positive wire in the center of the Dean’s plug. If in doubt, check
with a voltmeter; I have found new packs wired wrong. THE CENTER PIN
on your radio plug is not always positive. Airtronics has the positive
pin on the outside of the plug. THERE IS NO REVERSE PROTECTION on
any of our systems now. While reversed polarity shouldn’t hurt the module,
it could damage the sensor. Do not try and run the ignition off the same
pack as the radio.
We send most of the modules out without switch harnesses or
plugs. Any radio switch harness will work, just make sure you have battery
polarity correct before turning on the switch. When in doubt, check it
with a volt meter. Some radios have “plus” in the middle and some don’t.
Keep all the wires as short as possible and as far from any part of the
radio as you can.
We like to use a larger than 800 MA pack on the H.D. single
or twin system. If weight is not a problem, use,a 1200 MA or larger pack.
If you use one of the larger packs, make sure you use a charger rated for
the battery pack. You must be able to charge the pack at least 10% of its
capacity. A 1200 MA battery needs a 120 MA charger. You cannot leave your
500 MA battery charger on for a longer time and get the pack fully charged.
We use a variable charger as you can set just the charge you
want. If you get up in the morning and want to go fly and have not charged,
you can crank up the rate for a couple of hours. A field charger is very
handy too. Along with a proper charger. we couldn’t live without a good
ESV. To check your battery pack you must use an Expanded Scale Volt meter
with a 500 MA load. Sometimes we have as many as 8 aircraft at the field
at one time. It is hard to keep track of all these battery packs. The Ace
Voltmaster works very well.
INSTALLING THE IGNITION IN YOUR PLANE
1. Wrap the ignition module in foam, just as you do a receiver.
We usually put the module in a plastic baggie before wrapping in foam.
Protect from vibration. I have been asked if it is OK to mount the ignition
module on the front of the firewall ... beside or below the engine. This
is fine but you do need to protect the module from fuel and vibration.
I put a couple of cup hooks in the firewall and then place a 1/2" thick
piece of foam under the module. The unit is held to the firewall by rubber
bands ... simple but effective. Our big engines shake a lot. You MUST protect,
the module. Please don’t use Super Glue or RTV to glue the module solid
to the airframe.
2. Use a good 4.8 volt battery pack; don’t use an old klunker
from an old flight-pack. The majority of the problems with the ignition
system are caused by bad or undercharged battery packs. Use a charger rated
for the battery pack. Test with a load tester (ESV).
3. Keep the ignition module, ignition battery. switch and the
charging jack as far away from the receiver, receiver-battery-pack, and
the receiver battery switch as possible. Keep all wires on the ignition
as short as possible.
4. Do not use a metal push rod to the engine throttle or steerable
nose wheel. Do not use a metal throttle cable, even if it has nylon ends.
5. Mount the throttle servo at least 8” from the engine.
6. On the H.D. system with the ground pigtail, do not solder
a ground terminal lug to the shielded pigtail ... crimp this on. Solder
will flow up the lead and then it cannot flex, causing possible breakage.
If this ground lead comes off, the engine usually will continue to run,
which may cause interference to the radio. The best method is to use a
hose clamp and clamp the ground braid to the spark plug hex. DO NOT attach
the ground wire to a carb mounting bolt. Some of these bolts just go into
a fiber block and are not grounded.
If you want to remove the Bosch cover to get the spark plug
wire through a hole in the airframe, unsolder the ground from the Bosch
cover and unscrew the cover from the wire. If the cap doesn’t unscrew easily
you may have to heat it with a monokote gun to soften the sealant. After
you have installed the ignition in the airplane, use a new piece of heat
shrink on the plug wire, and screw the cover back on. The cover should
be screwed on about four turns. If you want to remove the rubber boot,
reach up into the boot with a small screwdriver and push the spring terminal
back out of the boot. Use some lube on the spring to help get it back into
the boot. You MUST protect the spark plug lead from chaffing. A fiberglass
cowl can cut the plug wire in just one flight. Use a piece of vacuum hose
or a grommet to protect it.
7. Make sure that none of the wires from the module or battery
pack are routed where they may pass over a sharp bulkhead, or are pinched
where vibration could cause them to rub through the insulation. This could
cause a fire in your airplane. It could happen with radio equipment also
I nearly lost my Laser with a short in the battery pack wires, so beware.
8. Range check your radio with the engine off and then running.
There should be less than a 15% decrease in range with the engine running.
OTHER SUGGESTIONS
1. If you are in a high humidity area, use some Silicone dielectric
grease on the spark plug and cap to prevent “arc over” onto the spark plug.
2. If you are running your engine inverted, run the engine as
dry as you can on fuel when shutting down for the day. Store the airplane
with the engine upright if possible. If you can’t store with the engine
upright, remove the spark plug for storage.
3. Do not install a micro switch on top of a servo as a radio
operated kill switch and run wires ahead to the ignition. If you want to
use a micro switch for a kill switch (a good idea) or smoke pump, use an
Ace switch box and a Ny rod to operate it.
If all else fails, read the instructions and trouble shooting
guide one more time. If you still have a problem, give us a call. We are
not always in the shop or office. Keep trying.
HINTS AND TROUBLE SHOOTING FOR ALL ENGINES WITH C & H IGNITION
SYSTEMS
1. The number 1 problem is still with the battery. Check battery
pack voltage with a good load tester. (We use the Ace Voltmaster.) Check
the battery pack voltage with an ESV. Then check voltage at the center
pin of the female 3-pin Deans plug coming out of the module. It s red,
white, black. Unplug the pulse switch from the module sensor switch, then
switch “on.” of course! This should be the same as battery pack voltage.
If the voltage is OK here, the battery pack and switch are OK. If no voltage
appears, make sure the battery and switch are wired correctly.
2. With the ignition switch on, ground the white wire on the
female 3 pin Deans plug (same plug as step 1). When you break this ground,
the ignition should fire the plug. If it does, then the problem is the
pulse switch or the magnet reversed ... check the pulse switch or replace
it with a known good one.
3. The black end of the magnet must go toward the pulse switch.
If up to this point everything checks OK, “flag” the pulse with the other
end of the magnet or use another magnet. Just pass the magnet back and
forth past the pulse switch. We could have marked the magnet wrong. If
this check makes the system fire, then the magnet must be turned around.
4. It is normal to hear a spark fire inside the module case
if you trigger the ignition with the spark plug wire removed and not grounded.
Do not do this unnecessarily. If you get a double spark once as the magnet
approaches. and once when it leaves the pulse switch, then the battery
is bad or needs recharging.
5. If after making the above tests you do not have a spark ...
send the module to us for repair or replacement. I would like to have the
battery pack switch harness and pulse switch also, if possible. If the
system came from an engine manufacturer, send it directly to C & H
for repair. If the system is under 90 days old it will be repaired or replaced
under warranty.
6. Make sure the chain saw type engines are using a resistor
type spark plug.
7. The new McDaniel spark plug 1/4x32 cap is working very well
and has just about stopped all complaints of R.F.I.
The McDaniel plug caps go on the spark plug very hard at first.
VERY IMPORTANT - With this cover you must push it over the hex
on the spark plug and then turn it to lock it on the spark plug.
When all else fails ... read the instructions. If after doing
this you still cannot get a spark or get your engine to run right ... do
not fight it for days on end ... or take it to your “local engine expert.”
Give me a call. If we cannot figure it out over the phone, I will be happy
to look at the complete set up and test run or test fly it if necessary
(in season!)
* NOTE: The Bosch cap will not work on the Champion RDJ6J, 7J, or
RCJ8.
It must be used on 3/4 hex short plug - Champ RCJY, Bosch R10,
NGK BPMR6A, or BMR6A
TIMING
Now for the fun part. If you are installing a C.H. Electronics ignition
system
with the CTC and are satisfied with the way your engine currently
runs at
full throttle, you will just need to lock your timing plate
at the full throttle position.
The easiest way to lock the timing plate is to drill (#36
drill) into the side of the
plate and tap for a 6/32 set screw. It is better to pull
off the prop hub and timing
plate to do this, but you don't have to. Just drill straight
in until the drill bit touches
the aluminum timing plate bushing. Now run in a bottoming tap
in until it stops.
Be careful and do not strip the threads. Now you tighten the
set screw and material
at the bottom of the hole will lock the timing plate.
If you would want to go back to the throttle coupled system
you will have to remove
the timing plate and clean things up as the timing plate
will probably bind up even
when you loosen the screw. You can use a bolt in place
of a set screw. If you do not
have a tap you can drill a hole and use a sheet metal screw.
Just screw it in and
lock the plate.
If your engine is set-up with a TCSA mechanical system or you need to set
the
timing for your CTC equipped engine just follow these
steps to set timing.
To install the CTC module, just unplug the pulse switch and plug the CTC
between the pulse switch and the ign box. The Deans plugs
are correct for a C.H.
Electronics ignition. That is all there is to installing
the CTC module.
If you have a C.H. Electronics ignition module with the
CTC built-in, just plug it in the
same way you would an ignition for a TCSA equipped engine.
The CTC module or the complete ignition module can be wrapped
in foam and tied
down.
For an engine using TCSA. set the timing to 28-32 deg Before Top Dead
Center (BTDC) at full throttle and 2-8 deg BTDC at idle.
This is approximately 26
degrees of total movement. To adjust the amount of movement,
move the push rod
in or out on the bell crank. To adjust the timing, change the
length of the pushrod.
For an engine using a CTC equipped ignition set the timing by at 28-32
degrees BTDC.
Most of the Sachs engine builders have settled on 30 degrees BTDC.
Ask us about other engine recommendations. The setting depends somewhat
on fuel altitude and outside temp.
The only way to set timing accurately is with a degree wheel.
A degree wheel print-out link is at the end of this page.
Buy a 6 inch protractor and a paper clamp at your local discount store.
Drill
the protractor for your prop shaft then cut out and glue
the degree wheel to the
protractor. You can also use a piece of lite-ply or what
ever you have around the
shop.
Attach a pointer to the clamp. Now you have a timing kit.

Here is another way I have found TDC for many years. Leave the spark plug
in
and bring the engine up on compression, let the compression
bleed off, on some
engines you may have to loosen the spark plug a little.
You will notice you have
about thirty degrees of free travel as the engine toggles back
and fourth past TDC
right in the center of this free travel is T.D.C. With the timing
pointer clamped onto to
a cyl head, set the degree wheel so that the free travel
at TDC is equal on both
sides of zero on the timing plate.
We have found the average engine to have about 20
to 30 degrees of free travel, if
there is more than this check your engine. Do this several
time to make sure your
pointer is on the zero mark when the engine is exactly
on TDC.
Keep in mind the pointer and zero degrees do not have to
be set at the top of the
engine, this is only a reference.
Making sure you do not disturbed you timing pointer, put a spark plug in
the
plug cap, ground the plug, hook up the ignition and turn
it on. Turn the engine over
and make sure you have a spark at the plug. Turn
the engine slowly and see when
the ignition is firing. Set the correct timing by moving the
timing
plate.
DO NOT RUN THE ENGINE WITH THE DEGREE WHEEL INSTALLED.
Now set up and start your engine. Observe all Warnings and Safety
Precautions and use a helper to restrain your airplane.
We should always wear a heavy glove when starting model engines, as we
do
not heal up a fast as we used to. Keep in mind any engine
with the right (or wrong
conditions) can hurt you.
Let your engine warm up and bring it up to full throttle
and hold this setting for at
least thirty seconds. You may have to set your carb a
little richer on the low needle
to get the correct throttle response. Now tach your engine
at fun throttle. Record
this figure.
If your R.P.M. is O.K Leave as is and go fly.
When you have your engine
set where you want it check the timing with a degree
wheel and record this for future reference.
If you want, we will set up your engine with the CTC and test run for best
performance for $35.00 service charge plus handling. This
is labor only and does
not include any ignition or engine parts. If you send your
engine, send the ignition
system, battery pack and switch.
Click here for printable timing degree wheel
CUSTOMER SERVICE
If you should need service on your system for any reason,
return it to the factory prepaid, with the following information. Your
name, address (UPS), phone number (DAYS), copy of your sales slip or invoice,
description of difficulty, and authorization to return C.O.D. or charge
card (if not warranty) for repairs and handling. Send complete system (Module
pulse switch, battery pack). Replacement parts are available from the factory,
and any part can be replaced by the factory.
LIMITED WARRANTY
C& H ignitions and related parts are warranted to be free
from defects in material and workmanship for a period of 90 days from the
date of purchase.
Limitation warranty on engines or engine work done at our shop.
The above warranty does apply to new ignition systems and related parts
installed at the time we work on the engine.
This warranty does not cover any incidental or consequential
damage or bodily injury caused by or resulting from a defect in material
or workmanship or other equipment failure. This means that no responsibility
is assumed for any damage or injury to any model or any other item or person
involved in the use of this equipment. Parts under warranty must be returned
postpaid to C&H and will be repaired or replaced at our option and
returned postpaid.
WARNING
C&H ignition systems are designed and built for model airplane
hobby use only. They are not designed for use in man-carrying vehicles,
nor should they be used in any ultralight, paraplane or home built type
aircraft. We assume no responsibility for damage or injury from the above
use. Large engine-powered model airplanes are not toys. Keep children away
and use extreme caution whenever flying or wnning engines. Please read
the safety report found in every Model Aviation Magazine.
Thank You, Bill Carpenter
C.H. ELECTRONICS INC., P. 0. BOX 1732, 3420 CHANDELLE BLVD., RIVERTON,
WY 82501