312H popping the fuse

[mrc 727]

hello men,  my friend tony asked if i could fix his 312H. it is model number 5112KE01  it keeps popping the 25 amp fuze.   tony bought a new key switch .this switch has 6 prongs. that did not help. i purchased a stens key switch plug/pigtail.   the old plug was not in good shape.  i soldered and shrink wrapped the wires and still i am blowing the fuse. can someone provide which colored wires go to which prong on the switch?  any help is greatly appreciated.  thank you  mike in mass.

[nylyon-(Admin) 7,121]

The owners manual should have a wiring diagram in it.  The RedSquare Manuals section has a downloadable manual for you if you don't have one:

http://www.wheelhorseforum.com/files/file/2531-tractor-1991-312-h-da-om-ipl-wiring-snpdf/

 

[gwest_ca-(File Mod) 10,514]

These diagrams are a little different as each circuit has it's own diagram
http://www.wheelhorseforum.com/files/file/5191-tractor-1991-312-h-wiring-detailed-492-4509pdf/

Garry

[doc724 924]

If a fuse is blowing, it implies that you have an overload or a short somewhere.  To help diagnose, you have to determine, does the fuse blow happen when the key is off, in run position or in start position?  Take a look at the demystification info sent by Garry.  The circuits (run, start, charge) are all broken down separately.  Sometimes, even with this info you have to look at the complete schematic.  Does your machine have headlights?  If yes, these are powered in the run position.  The lights do not have to be on if there is a short between the +12V supply and ground.  On my C141, there was a wire that followed the steering shaft down and ultimately went to the headlights.  The wire was pinched between the shaft and the battery tray and chafing of the insulation was beginning.  Get a good meter and begin tracing each wire.  It takes patience, but ultimately you will get to root cause