Kioti Ignition Switch

I prefer to call this a key switch because Diesels don't actually have an electrical ignition system.  Still, many people call it the ignition switch so the terms are essentially interchangable.

The Kioti key switch is a frequent source of problems.  The switch has a mechanical section with the tumblers (for the key) and an electrical section with attached wires which end at the connector. 

The electrical section is the problem.  Below is a photo (provided by landedakioti) of the electrical section of a dirty switch.  On the left piece, note the electrical contacts that are attached to the wires from the connector.  The right section is the (dirty) copper disk with raised semi-circular tracks.  When the two sections are mated, a spring holds the disk firmly against the electrical contacts. As the key is turned, the disk rotates to make and break electrical continuity between contacts as the raised tracks wipe or miss the various contacts.
  Image of switch electrical section

Here is a photo of that same copper disk after the owner cleaned it.
clean switch disk


The problem appears to be caused by the grease that inhibits corrosion and lubricates the disk and contacts.  This grease gets hard with heat and age and it also collects dirt from dust in the air.

As a quick fix, squirting WD40 or Fluid Film into the key hole and then rotating the key several times will often disolve hardened grease, wash away dirt, and allow the switch to function correctly.  If that doesn't work, the switch can be replaced or rebuilt.  Note that there is more than one version of this switch with different electrical functions.

The switch is easy to remove for replacement with a new switch or for disassembly and cleaning.  The switch is not hard to disassemble if you are careful to note the orientation of parts and not break or lose any parts.  WARNING: some parts are spring-loaded and easy to lose; so use care.