2. Spark.
a. Start by pulling a spark plug wire off any spark plug. Hold the wire about
1/8" to 1/4" away from some good piece of metal (not the carb) and have the
helper try and start the engine. Do you see a spark?
If yes, you're good to go. If not, it's electrical and we need to find out
what's not working.
b. Now remove the high voltage wire that goes from the coil to the
distributor at the distributor end. Hold the wire about 1/8" to 1/4" away
from some good piece of metal (not the carb) and have the helper try and
start the engine. Do you see a spark?
If yes, then the problem is in the distributor. Usually the rotor button
shorts out allowing the high voltage to go to ground through the distributor
shaft. Replace the rotor button and repeat test a. (Note: it won't hurt
to replace the distributor cap, rotor button, points and condenser at this
point and is a very minor investment - usually under $30 for the parts.)
If no, then the electric field is not being generated in the coil. This
can be due to a bad coil or a problem in the points (or electronic ignition
module) or the wiring.
c. If you have pionts, you need to pull the distrubitor cap. Connect the
positive lead from a voltmeter to the low voltage (12v) wire connected to
the points. Have your helper turn the ignition to the run position.
Look at the reading on the voltmeter. Is it reading 0? If so then the
points should be closed. If the meter is reading 12V then the points
should be open. The pionts job is to open and close, creating a path
to ground for the 12V when closed.
If the point are open, and the voltage is not reading 12V, then the points
have shorted. There is usually plastic or cardboard insulator that needs
to be between the pivit post and the points, and sometimes near the 12v lead
from the coil. This will depend on the engine. If in doubt go ahead and
replace the points and condenser.
Check the low voltage (12V) wiring from coil to the distrubitor. Make
sure it isn't broken or shorting out anyplace.
d. The condenser is very difficult to trouble shoot. It's easier to just
replace.
John T. Blair WA4OHZ email: jblair1948@cox.net
Va. Beach, Va
Phone: (757) 495-8229
48 TR1800 48 #4 Midget 65 Morgan 4/4 Series V (B1106)
75 Bricklin SV1 (#0887) 77 Spitfire 71 Saab Sonett III
65 Rambler Classic
Morgan: www.team.net/www/morgan
Bricklin: www.bricklin.org
If you can read this - Thank a teacher!
If you are reading it in English - Thank a Vet!!
|