wiring on coil

I have a WC that has a dist. on it. When checking the system the pos. side of the coil lights up on the tester. The neg. side also lights up. Tractor won't start. It was starting when pulled and would start after that during the day. With the test light coming on on both side of the coil is the coil bad or the elec. ign? Any help would be appreciated.

Sounds like you need a 101 on how things work and lay that meter to the side it is getting you lost. Pull the center wire out of the distributor cap and hold it about a 1/4 inch from the block. Try to start it. You should get a blue/white spark from it. If you do not then pull the cap off and check that you get a spark when you open and close the points by hand. If no spark at the points then they are burned or dirty of flat out bad. Test lights and meters have there place but many time not when messing with engines.

Old, it doesn't have points I wrote elec. ign (electronic ignition) sorry I didn't spell it out. We put the coil wire up to the block and there is no spark. I'm trying to figure out if its the coil bad or the electronic ignition that's bad. Thanks

That is easy to figure out also. Just short the wire going to the distributor and then remove the ignition side wire and touch and remove the ignition side and watch for spark from the center wire

(quoted from post at 21:43:42 05/22/15) That is easy to figure out also. Just short the wire going to the distributor and then remove the ignition side wire and touch and remove the ignition side and watch for spark from the center wire

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old, can you tell it step by step? I don't follow what you are saying.

Well if the points are closed and you take a wire and touch the ignition side of the coil off and on you should see a small spark every time you touch and remove that wire. That is a simple way to test the points. Then you turn the engine enough to open the points and try that again. If you still get a spark you have a short in the distributor. Sort of a poor mans test system that takes no tools to do

400 guy, the elec switch may be bad, but here's how to eliminate it and test just the coil (independent from any elec switch or points).

COIL TEST

Of course, you must have hot battery voltage (with respect to frame ground) on the coils + INPUT when the ignition switch is ON.

Remove the coil wire out of the center top of the distributor cap (leave coil end intact into the coil) and place it instead within 1/4 inch or so away from the engine or other tractor steel frame.

Remove the small wire from the coils - OUTPUT where it wires to distributor (leave attached to coil but removed from distributor).

WITH IGNITION ON AND VOLTAGE ON COILS + INPUT, EACH TIME YOU MOMENTARILY GROUND THE LITTLE WIRE FROM THE COILS - OUTPUT (that used to go to distributor) THEN REMOVE IT, THE COILS HV WIRE (coil wire out top of distributor) SHOULD SPARK THAT 1/4 INCH GAP TO TRACTOR. IF IT DOES THAT THE COIL IS PROBABLY OKAY.

ELEC SWITCH TEST

If you place a DC test light on the coils + INPUT, it should light and stay lit anytime the ign switch is ON.

Now place the DC test light over on the coils other - OUTPUT (where it wires to distributor) and crank the engine over

THAT LIGHT SHOULD FLASH ON AND OFF AS THE ENGINE IS CRANKED OVER. If it stays on all the time or stays off all the time the switch may be bad or isn't wired or installed correct.

NOTE en elec switch is polarity sensitive, it must match yoru tractor polarity (Pos or Neg ground) and if not it amy be fried.

NOTE the above troubleshooting is for Neg Ground

Got it???

John T