50 john deere wiring schematics

I have an old 50 John Deere, have had it for years, runs great! It sat out one night in the rain, now no spark to the plugs.
It was time to replace the distributor cap, rotor, and I also replaced the coil, still no spark. Any thoughts?
Also what is the wiring schematics for this tractor to the coil, distributor, etc. It is a positive ground.
Thanks.

I have a John Deere 40 with an ignition switch that acted up two years ago. I just switched it on and off multiple times to clean the contacts and it has worked ever since. It might be worth a try to see if you get spark. If you do it may be time for a new switch. I should change mine.

"[b:654c4848f0][i:654c4848f0]<font color="#6699ff">Also what is the wiring schematics for this tractor to the coil, distributor, etc.[/i:654c4848f0][/b:654c4848f0]</font>"

Take a look at the [b:654c4848f0]Lamps and Wiring[/b:654c4848f0] diagram below.







"[b:654c4848f0][i:654c4848f0]<font color="#6699ff">It was time to replace the distributor cap, rotor, and I also replaced the coil, still no spark. Any thoughts?[/i:654c4848f0][/b:654c4848f0]</font>"

Presuming you have a gasoline or all fuel tractor, take a look at the [b:654c4848f0]Lamps and Wiring[/b:654c4848f0] diagram above.

Note that current/power flows from the NEGATIVE battery terminal to the NEGATIVE terminal on the ammeter.

Note that current/power flows from the POSITIVE terminal on the ammeter to the BAT terminal on the ignition switch.

Note that current/power flows from the BAT terminal on the ignition switch to the IGN terminal on the ignition switch.

Note that current/power flows from the IGN terminal on the ignition switch to the input terminal on the ignition resistor.

Presuming there is current/power flowing as described above, then start by turning the ignition switch ON to the first position.

Using a test light, check for current/power at the input terminal on the ignition resistor.



If there is no current/power at the input terminal, then check the IGN terminal, BAT terminal, both POSITIVE and NEGATIVE ammeter terminals, NEGATIVE terminal, and last the POSITIVE ground,

If there is current/power at the input terminal, then check for current/power at the output terminal on the ignition resistor.



If there is no current/power at the output terminal, then replace the ignition resistor.

If there is current/power at the output terminal, then check for current/power at the NEGATIVE terminal on the coil.



If there is no current/power at the NEGATIVE terminal, then repair/replace the green lead wire connections.

If there is current/power at the NEGATIVE terminal, then check for current/power at the POSITIVE terminal on the coil.



If there is no current/power at the POSITIVE terminal on the coil, then replace the coil.

If there is current/power at the POSITIVE terminal on the coil, then check for current/power at the breaker plate to housing screw on the distributor.



If there is no current/power at the breaker plate to housing screw on the distributor, then repair/replace the black lead wire connections.

If there is current/power at the breaker plate to housing screw on the distributor, then check for current/power at the breaker plate to housing screw retainer inside the distributor.



If there is no current/power at breaker plate to housing screw retainer inside the distributor, then repair/replace the breaker plate to housing gasket.

If there is current/power at breaker plate to housing screw retainer inside the distributor, then check for current/power at the breaker points.



The following is one method of checking for spark from the distributor.

Presuming that the gap has already been set on the breaker points, you might consider cranking the engine with the distributor cap off and check for spark at the points.

Replace the rotor and distributor cap.

<font color="#ff0000">[b:654c4848f0][i:654c4848f0]CAUTION:[/i:654c4848f0][/b:654c4848f0]</font> Make sure the fuel is turned OFF and/or drain the carburetor and/or cover the open spark plug holes.

Remove the spark plugs and attach the plug wires.

Lay the each spark plug either on the block or frame.

Crank the engine and check for spark at each spark plug.

If there is still no spark, then replace either the plug, plug wire, distributor cap, or rotor.

Hope this helps.

You can carefully bend the tabs and get the ignition/light switch apart to clean the internal contacts.

Try cleaning the point contact surfaces with a thin piece of clean cardboard, like a cereal box, or a piece of clean paper folded over several times.

Thanks