No announcement yet.

Spark Tester

  • Filter
  • Time
  • Show
Clear All
new posts

  • Spark Tester

    Yesterday I borrowed and used a Spark Tester on my car between the coil wire and distributor cap. With the wooden peg I moved the wire inside the tester and saw that I had a spark but could move it so that the spark seemed to break up and there for moved it back to the original position.
    Question is what did I really accomplish by doing this other then to see there is a spark from the coil wire to the distributor cap?

  • #2

    A good spark tester does much more than telling you if you have spark. This is mine and with it i can determine A few more things from experience. Such as spark intensity, erratic spark
    A large easy to see neon viewing bulb is essential

    3~ Tudor's & 1~ Coupe
    Henry Ford said,
    "It's all nuts and bolts"
    "Start by doing what's necessary; then do what's possible; and suddenly you are doing the impossible."

    Mitch's Auto Service ctr


    • #3
      You also discovered that if you set the gap to wide from cap to rotor, or the gap on the plugs too wide, the spark will fail.

      Which is also why I prefer my shaved cap to a clear cap because with that in place you can accurately measure the distance between rotor and cap, since it does hold the distributor body fixed instead of possibly rattling around on the top of the distributor.
      Last edited by DaWizard; 08-27-2017, 09:53 PM.
      You wana look waaay far up da road and plan yer route because the brakes are far more of a suggestion than a command!


      Related Topics


      • Mitch
        Checking for Intermittent Spark
        by Mitch
        Diagnosing a high speed driveabilty problem can be tougher, because you usually cannot replicate it in your driveway. The first thing i like to know is what system is causing the issue spark, fuel or mechanical. Once this is determined one can then start troubleshooting that particular area. I use this style spark tester that you can get from Amazon, which enables plug wires to be snapped onto each...
        You do not have permission to view this gallery.
        This gallery has 1 photos.
        10-22-2017, 11:42 AM
      • wensum
        Front two plugs fouling
        by wensum
        My speedster has a modified motor with 7:1 head and twin Stromberg carbies off early Holdens amongst many modifications.
        It has run strongly for 15,000 miles but is now fouling the front two plugs at idle and there appears to be no spark at idle.
        I can short out the front two plugs with a screwdriver with only a very weak spark just visible whilst the rear two have a strong spark and...
        You do not have permission to view this gallery.
        This gallery has 3 photos.
        07-13-2020, 11:52 PM
      • fixitgood
        no spark
        by fixitgood
        I have lost the spark from the coil
        10-08-2021, 07:32 PM
      • DBaldwin
        Hugh’s coupe
        by DBaldwin
        Yesterday I went to help Hugh get his model A started as it had sat for a bit due to his foot surgery. First off the zenith carb which was recently rebuilt had a stuck float so no gas that was quickly remedied. Still it would not start. Checked voltages from battery through to distributor. All points good. Checked and rechecked point gap also good. Checked timing once , twice , three times. Here’s...
        10-27-2022, 07:54 AM
      • Hank B
        Poor spark to #4 Cylinder
        by Hank B
        I have been chasing a gremlin on my coupe the last coupe of days.
        My perceived problem was noticed on my way home from town this week.
        The car runs quite well at low speeds and idle, but seems to be starving for gas/air or spark or both when under some load.
        It lost it's otherwise peppy attitude.
        I diagnosed most everything in the engine compartment, changed out one item...
        05-08-2022, 07:22 PM
      • Rob Doe
        Spark plugs tester tool
        by Rob Doe
        Page 1-4 of LES Andrew's Troubleshooting Guide shows what appears to be an incandescent light bulb with a ground clip being used to test for spark at the plugs. Is this real or a fun joke?...
        09-16-2021, 02:04 PM
      • EdwardM
        spark plug resistance?
        by EdwardM
        I am having issues with my model a staring, it doesn't.
        when cranking over ampmeter deflects = power going to points.
        remove plug terminals for spark check = good spark
        but to check if plugs are firing I measured the resistance from the insulated post to the terminal post and I measured, 738 ohms, 37 ohms, 1.4 ohms, .6 ohms.
        these are new campion W16Y plugs. I...
        09-26-2021, 06:16 PM
      • Fordman
        What would cause this spark issue at the plugs?
        by Fordman
        What would cause the engine to run on only #3 and 4 cylinders?

        With the car running I pulled the spark plug lead from the top of each spark plug about 1-2 inches and got a good spark at each plug.

        But, when I totally removed the wire from plugs 1 and 2 the car made no change in running or sound or rpms. 3 and 4 when the plug wire was removed the car immediately dropped rpms...
        06-24-2022, 12:31 AM
      • Soapy
        Replacing the spark plug wires on my 1955 F-350 Truck
        by Soapy
        Whenever I have replaced spark plug wires before this, it was usually a very simple process of pulling one plug wire at a time and taking the new wire back to the distributor and replacing the old with the new wire at the distributor cap. This is certainly nothing like that. Although the service manual only spends a few short sentences, on the process, the diagram shows the wires locked together in...
        12-14-2020, 10:28 PM
      • dmdeaton
        Spark Plugs
        by dmdeaton
        What spark plugs are you guys running and where is the best place to order some?
        08-29-2017, 03:39 PM