Electrical No Spark

Discussion in 'Classic Mustang Specific Tech' started by wubba, Dec 14, 2012.

  1. So yesterday I was able to jump my starter to get the engine to turn.

    Changed the spark plugs and the wires. Added a new distributor cap.

    Engine wouldn't start.

    So got my spark plug tester out and put it inline - and I am not getting any spark.

    So the coil that was in there was rusty and nasty looking - so I replaced it. Still no spark.

    Stumped at where to begin to look.
  2. Check the starter solenoid, and voltage regulator. Did you check the battery? How's the wiring?
  3. Battery yes, but fully charged battery. Cranking on a no start situation weakens batteries pretty quick. Do a search on a "voltage drop test", that should help you along.
  4. start by checking to see if you have voltage through the coil. meaning pull the negative lead, and with the key on run the test leads from the coil to ground. if you have no voltage, check to see if you have voltage to the coil. if you do then you still have either a coil problem or a ground problem. if you have voltage through the coil, the check the points for proper opening and adjust as necessary.

    if you have no voltage to the coil, then check the wiring back to the switch, and check the ignition switch, testing for voltage at each step.
  5. Guys - thanks for the reply.

    Here is what I have done.

    I replaced the voltage regulator - it was rusty and fully of junk.

    I took my test light and check voltage on the + of the coil when I jumped the starter (I am using a screw driver to touch the positive side of the battery to the low side of the solenoid to spin the starter) and it lit up. I then did on the - side of the coil and it lit up.

    So following the wire to the distributor - I took the cap distributor cap off and tested with my test light to see if it lit there - and it did. Then traced it farther to the capacitor and it lit there too.

    But still no spark.
  6. look inside the dist.cap there should be a carbon button it the center.these somtimes break or fall out when the cap is removed .check the rotor it may be burned or broken.
    edit - the points may not be opening and closing.
  7. I already replaced the rotor and the cap.

    I haven't done the points or condenser - but I was getting spark there.
  8. try the coil wire then ,leave it in the coil but take it out of the dist. cap. hold it about a 1/4 inch from a bolt or somthing on the motor...not the carburator .turn the motor over with the key on and see if you get a spark. if you do you should have power to the plugs. keep your fingers back from the end of the coil wire or you will get a jolt:crazy:
  9. wubba, you need to test if you have voltage to the coil with the key on and not jump the starter solenoid. also how are you checking for spark? did you disconnect the coil high voltage wire and hold the end close to a ground? if so then perhaps the high voltage wire is bad.
  10. Well - I figured that points were bad in the distributor - so I went ahead and replaced it with the electronic ignition from Petronix.

    I also bought the coil from them.

    It only took about 10 minutes to install - and BAMM - I got spark on my tester. So I hooked up everything and go then engine to start - rough of course.

    Thanks for the help guys.
  11. CONGRATS! Always great to hear them fire up! Sucks when they don't start...I know all about it.
  12. thats great . on more than one occasion i have discovered the condenser was bad.
  13. good work. like horse sence, i too have found that a bad condenser will prevent a spark from occurring. and on more than one occasion as well.