John Deere 318 b43g not firing help please

I have installed new coil, new condenser and new points.
Still no fire. With the key switch on, there is fire on the - wire from the coil to the points. Thanks in advance. I have spent a fortune on this thing and have never got to mow with it.

(quoted from post at 23:18:33 07/12/17) I have installed new coil, new condenser and new points.
Still no fire. With the key switch on, there is fire on the - wire from the coil to the points. Thanks in advance. I have spent a fortune on this thing and have never got to mow with it.

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Is there current through the coil primary when the points are closed and no current through the coil primary when the points are open ?
Type and condition of the secondary wires and plugs ? Plug reach and are they non resistor ?

Usually the points are closed, except for TDC on a piston when they break open to fire the coil, so I would expect there to be NO VOLTAGE on the wire from the coil to the points. If there's ALWAYS voltage there (even when points closed) the points may not be fully closing or there's a break in the circuit from coil to and thru points to ground or the distributor or points aren't getting a good ground. A test lamp on the coils output to distributor with ign on and engine slowly cranked over should flash ON (points open) and OFF (points closed)

If ??? this is a standard battery powered coil ignition NOT a Magneto my Ignition Troubleshooting Procedure linked below will help find the cause of no fire. Does the 318 use a battery powered coil and points ignition????????????? or some sort of a magneto??? The link below is ONLY for a battery powered coil and points ignition system. Some small tractors and mowers use a KILL SWITCH which grounds out the coils output to stop the engine but if that were the problem there wouldn't be voltage on the coils output, it would be shorted to ground !!!!!!!!!

ARE YOU SURE THE POINTS ARE CONNECTED PROPERLY ??????????

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=5745

John T
John Ts Ignition Troubleshooting

Thanks for the help, I'll have to check for current. It has the factory wires and caps. I know there is fire on the negative wire from the coil to the points when the key is on. Thanks again

It's just a simple points ignition with no distributor the plug wires are on the coil. There is only two wires on it other than the two plug wires. The negative post on the coil runs directly to the points and the positive post on the coil runs to the key switch.
im sure I installed the points properly, only one wire to them. And they are breaking. Thanks again for helping. I will look at it this afternoon and check the current when it is cranking

You're welcome. Its pretty simple then. Put a 6/12 test lamp with the alligator clamp on frame ground,,,,,,,,,, turn on ign switch,,,,,,,,,,,,,, with probe/light you should get voltage on the coils + input at all times,,,,,,,,,,,put test probe/light over on coils other - output to points, and you should get 0 volt no light when points close and battery voltage light on when open. If the light never goes out the points arent conducting current to frame ground when closed as they should. Open wire or no ground to points or not fully closing or just bad??

With ign on and voltage on coils input from ign switch, if you take a jumper wire to coils - output, each time you touch it to ground but then remove it the coil should fire if alls well. That's same as if points close and conduct current then open it should fire. You might take an insulated probe and close n open the points to see if it fires each time closed but then opened???

John T

just a real quick check.
but try new plug wires. the old ones if they are original will be all cracked and broke inside
this is what was wrong with my 318.
took me a long time to diagnose.
new wires and runs like a top