1420 cub cadet mower wont turn on

There is a possibility that the clutch coil is opening the circuit only after the machine heats up, so you might want to mow with yer VOM in yer pocket until it does it, then test immediately.

Thoroughly check every stinking one of those bayonet-style clips in the circuit. They do get dirty and/or loosen the connection. Use contact cleaner to clean them, or emery cloth where you can get at the spades.

You can temporarily short across safety switch connectors to see if they are the problem.

Last, it may come down to running the wires and checking each with the VOM for a short. You can do this through observation without a schematic, if you are carefully observant of the color codes, etc.

But my bet is bad connector or bad clutch coil, if you have replaced the switches already.

Good luck.

If the problem is not caused by poor charging/dead battery:

Test yer ignition switch in the start and run positions with the wires disconnected. If it is not working in one or both, shoot contact cleaner in it from the back and work it, shoot some more and work it...do that 3 times or so, and test it again. That contact cleaner saves a lot of new switch buying, works for the safety switches, too.

If ign. switch OK, take a battery charger, ground it to the engine, and just touch the positive to the starter post for a second. If it turns over, starter is OK.

That gets you down to the solenoid or a short/bad connection in the wiring. Check and clean all your connections, including the ones at the battery. Any push-pin connections should be thoroughly inspected. Don't neglect to clean up all the ground connections, too.

If the battery is dead or you do not get good charge (should read 14 +/- VDC across battery terminals with engine running):

Test the engine charge coils by disconnecting the wire clip and checking ohms across the terminals (continuity). Also, ground one VOM wire to engine and check each of the coil terminals for shorts to ground (should not be any reading). If that's OK, it may be either bad connections (common) or faulty solid state regulator (less common). Clean ALL connections before suspecting the regulator.

The full regulator test is outlined in the Kohler Engine Service Manual from your dealer. There are several types of regulator, so I won't go into that here.