IGNITION SYSTEM

The ignition system should be checked to verify you have good spark at each plug and correct any problems. With the engine running, remove and replace each plug wire at the spark plug. Listen for a drop in RPM as a plug wire is removed. The engine should then return to normal when the plug wire is replaced. If you remove a plug wire without a corresponding drop in RPM, you have a dead cylinder. If that is the case, it might be a fouled plug, bad plug wire, incorrect firing order, bad distributor cap, worn distributor, stuck valve, bad rings, burned piston, ... Bad wires are usually pretty obvious. Its hard to ignore the electroshock therapy when you grab the wrong thing or the light show you see with the engine running at night. If the problem only shows up when there is wet weather or high humidity, make sure your distributor cap and wire boots are in good shape.

If you are having trouble with weak spark, no spark, or burned coils, you may find some helpful information on this page CLICK HERE.

If your ignition switch is more than a couple of years old, it's probably a good idea to replace it. These tend to get corroded and any resistance added by a bad switch makes for a weak spark. Sometimes a switch will test ok with a test light or ohmmeter and still be bad. If there is any question, just replace it.

Use spark plug wires with a solid copper core NOT automotive resistor type wires. Cylinders are numbered 1, 2, 3, 4 from front to back and the firing order is 1, 2, 4, 3. YES, it's 1, 2, 4, 3. That is not a typo. Replacing wires one at a time can keep you from mixing them up, but it is always a good idea to check the firing order when you get done. If your tractor starts and seems to idle fine, but does not want to pull a load, check the firing order.

Check and see if your headlight switch works when the ignition switch is off. If so, yours is wired so that the headlight current does not go through the ignition switch. I believe this is the best way to do it. The ignition switch should last longer without the added load of the lights. The only down-side is you have to make sure both switches are off when you park it. But then, most people think being able to use the lights without turning the ignition on is an advantage. If you leave the ignition on to use the lights with the engine off it can fry the coil.

CAUTION! The start pushbutton works even if the ignition key is off! The start pushbutton grounds the wire from the start terminal on the solenoid. That is different from the way the automobile solenoids work. This means you can crank the engine even with the ignition turned off. DO NOT replace the original ignition switch and start pushbutton with an automotive type ignition switch. This will bypass your neutral safety built into the pushbutton start switch.