430 no spark

FSA1953

Member
Trying to figure out why I have no spark at the plugs. New coil,points,condenser,plugs,wires,cap and rotor. Any ideas?
 
Run a hot wire directly from the battery to the coil. If that gets you spark, back check all the wiring and ignition switch. It might be as simple as a crimp-on connector not making a connection to the wiring. If you have crimp-ons, go through them all and solder them, after pulling the insulator cap back up the wire. If that doesn't help, pull the wires off the switch, and check continuity across the terminals with a volt/ohm meter, as you turn the switch on and off. If that doesn't help, start looking for a short in the distributor. My Continental had a direct short between the point/condenser plate, and the advance plate under it. A piece of plastic milk jug isolated the plates and it purrs like a kitten.
 
I have power to the coil tested with light pos side stays steady and neg side pulses when trying to start so I know the points are working. Should the points spark when opening and closing?
 
Test light should blink on either side of the coil since all a test light see if a wire and that is all a coil is, and a bunch of wires wound around them self. Put the old condenser and see if it works. Now day you stand a better chance of a condenser being bad out of the box then being good
 
With key turned on pos and neg test light stays on, crank over only neg blinks pos stays on. With new condenser in the coil pos and neg would stay on while cranking. Put old back in neg blinks when cranking. Was like that before I replaced everything. Still don't know why no spark to plugs unless new plug wires are junk.
 
(reply to post at 00:44:58 02/28/21)
The coil terminal connected to the ignition switch wire should stay on whenever the switch is on , the distributor side should pulse when turning it over with 12 V supplied, and the light pulse should be more brilliant than just a 12V light. The reason for this is the condenser discharges back into the circuit and the stored voltage much exceeds the system voltage, as the magnetic field collapses in the coil when the points break it induces a much greater voltage in the coil which then is absorbed in the condenser until the voltage collapses to the point where the condenser unloads back into the primary side of the coil. If the system did not flash with the new points and condenser , just stayed on solid the points were not gapped properly or the contact faces were dirty/ insulated. If the condenser does not cause a bright flash it is not good. As Old stated, condensers have been a problem in the most widely distributed tune up kits, I get my points and condensers from the auto parts stores. On a couple occasions I have had the connection on the condenser lead at the screw stick up far enough that the steel cover would short it out, I always bend them over after install. Rotate the engine till the distributor cam lobe is under the rub block on the points and set them to .020.
 
I was reading your post and what Mel said. Did you pull your coil wire from the cap and see if you have spark to ground. If you have carbon wire it may be open. Now if you have spark there then look at the cap carbon tip in the center of the cap make sure it is go and contacting your rotor.
 

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