I am trying to get a 79 351w running. currently no spark. I replaced the coil
and ignition module. I can get a spark by hooking the coil - to ground and
putting +12 on the + side for a second, so I do have a base for what spark looks
I am not sure how to test the Hall effect gizmo that is in distributor. I think
it is just windings, so this should have lit the lapmp:
+12 -- lamp -- gizmo -- ground
but it didn't.
If not, how do I test?
The winding is about 1000 ohms, there probably wasn't enough
current passed thru the windings to allow the bulb to glow.
Invalid test not supported by Ford.
Ohm meter, check for resistance between 800 and 1000 ohms, if
okay, connect a voltmeter set to AC volts, crank engine, you
should see at least 1 volt (one) AC.
Three wires pass into the distributor bowl, the black one is
attached to a ground screw, remove the screw and clean everything
nice and shiny, remove distributor from block, clean all areas
where the distributor and block contact each other.
This ignition system will not function if this ground path is
corroded in any way.
Also, this and all other Duraspark systems shut down if voltage
is below 10 volts, so hang your volt meter on the battery set to
DC volts and watch the battery voltage while you crank the engine.
It can NOT go below 10 volts, if so, replace the battery.
Do not assume just because the engine cranks good that the
voltage is above 10 volts, measure it!
I was using a remote starter switch, and pulled the orange (or faded red) from
the solanoid to hook up the remote. turn key on, hit switch, no spark. replace
orange, hit switch, spark. looking at the diagram again I see the 'start' goes
to the ignition module too.
I can understand some adjustment to the timing when it is being cranked, but why
the @#$@ would it _not spark_ when the ignition is on and the motor is turning
Carl K wrote: (79 351w)
Trying to get it running, but no spark. Replaced coil and ignition module.
I can get a spark by flashing the coil with 12V. Was using a remote
starter switch, and pulled the orange wire rom the solenoid to hook up
the remote. Turn key on, hit switch, no spark. Replace orange, hit
switch, spark. Looking at the diagram again I see the 'start' goes to
the ignition module too.
Why wouldn't it spark with the ignition on and the motor cranking?
Because the module is not getting 12 Volts from the ignition switch in
the RUN position.
You confirmed that the coil works, the module works, the starter works,
and the distributor works.
Three most probable causes of the problem:
1.) Bad ignition switch.
2.) Bad 12V supply to ignition switch
3.) Bad connections from ignition switch to module.
4.) Broken ignition resistor if so equipped.
What color are the wires coming out of the module?
Normally the white wire will be hot when cranking only, red will be hot in run
There's also a wire connected to the starter solenoid to bypass the ballast
during crank mode.
The wire you're pulling is probably the ballast resistor bypass-I don't have the
diagram with me to verify the color. Look at the diagram-if that wire is pulled
no voltage to the coil during crank.
Because the module is not getting 12 Volts from the
ignition switch in the RUN position.
Carl K wrote:
Um, you didn't answer my question. I know how to
make it spank. Just wondering why it is the way it is.
Um, I did answer your question, as did several other
Rodan. <------ Falls for a TROLL every time.
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