John Deere 4010 - No Spark

[Anonymous Poster]

I can't get a spark of any kind from the coil on this 4010 Propane tractor. I've changed the coil, condesor, points, wires and even been advised to add a 12v to 9v reducer (ceramic device) in the positive wire to the coil. All of this and still nothing from now a third coil installation! The 12v battery is good and the starter turns the motor OK. I'm showing voltage to the coil and the points. Any ideas??

 

[geneP]

I'm not real familiar with tractor distributors, but on some auto distributors a wire can short out under the points plate.

 

[craigb]

Is this a multi cylinder motor with a standard distributor? If so have you checked to make sure the distributor turns when the motor turns? Probably so but I would then clean and check all my ground wires between the distributor, motor, and battery. Clean the area under the points thoroughly as this completes the circuit. If when you turn the key on and you are getting voltage to the coil side of the points then try snapping them from open to closed. When you do this have the coil wire pulled out of the distributor cap and close to a good ground. When the points close after being snapped open you should get one spark from the coil. If not then you probably have a ground problem or low voltage to the coil. Measure battery voltage and compare it to voltage at the coil and points. Some systems do use a reduced voltage to the coil to reduce coil temperature over extended operation times. More voltage through the coil means higher spark output but reduces coil and point life. Hope this helps, Craig B.

 

[heehaw]

the rotor sends the spark to the plug wires; is it good?? the distributor cap can cause the same problem, look at the contact points under the cap, for the rotor, and check for a cracked cap??
let us know what you find
heehaw