john deere key switch getting hot

I have a john deere 314 the battery is charging at about 13 to 14 volts . But it seems like when u turn the pto on the key switch wants to get really hot I don't want to run it to long because it may burn the switch up thanks scott
 
If the coil in the electric clutch is beginning to fail, it will draw higher and higher amounts of current through the key switch will can result in that switch heating up. Then again, maybe the switch is the problem because it is no longer making good contact internally and the heat is the result of a bad connection. What you need is an accurate ammeter so that you can measure what the clutch is drawing when it is engaged. The switch is the cheaper of the two components so you could just replace the switch and see if that cures the problem or not. If the heating continues, then I would conclude that the coil windings are shorting together and the clutch will fail shortly.
 
I think Tom nailed it.

I just want to add that you can check the resistance of the clutch coil with an ohm meter. At the clutch plug, If it has 1 wire, you check between the wire and the ground. Either a ground on the frame or at the battery. If it has 2 wires you check between the two wires. The absolute minimum resistance in the winding that is o.k. is about 2.5 ohms. 3 ohms to 5 ohms is better.

It is also a good idea with the 2 wire clutch to check the resistance between each wire and the ground (or the clutch case). You should get an 'open circuit' or infinite resistance reading.
If your ohm meter finds a current path between either wire and the ground (or clutch case) it means that the windings are shorting to the clutch case. And in most cases the only electrical path the clutch case has to ground is back up the crankshaft into the engine where it erodes the pto bearing due to arcing. Not a good situation.
 
WAY too much drama! Simply measure the CURRENT drawn by the electric clutch.

If it's over the 4 to 7 Amp range the clutch "field coil" is shorted.
 
It isn't real tough (or expensive compared to buying potentially unneeded parts) to find an in-line ammeter that will read 20 Amps (a panel mount, as was used in an older tractor for example).

I am lucky to have a couple of sets of old-fashioned "DC inductive ammeters" in my electrical toolbox similar to the set pictured below. (Even though that name is sort of a misnomer!)

You simply hold the wire in question aligned in the guide at the back of the meter, and it reads the current flowing through the wire.

<img src = "http://i.imgur.com/Y9i4dvU.jpg">
 
That has been true in the past, however, nowadays MANY readily-available clamp-on ammeters can measure DC Amps.

Typically, they use a "Hall-effect device" to read the magnetic field surrounding a DC conductor.
 
Also, once you've had one, you will wonder how you got along without it. They're handier than a pocket on a shirt and make quick work out of figuring out what's going on in a circuit, eliminating a lot of guesswork!
 
I believe in them. I assume some error, but a dragging starter is very different than a good one. and 10 amps is not a good ignition load. They are inexpensive as well. Jim
 
One thing not mentioned. The plug on the back of the switch. Wiggle the plug off and see if it is fried. The clutch should be in the 5 amp area for a big one. With the engine off just look at the AMP gauge in the dash if you have one and turn the key and pull on the switch. If no gauge then follow the other advice. I had a switch fry one two different machines from water "rain" damage.
 
I paid about $80 for my Sears clamp meter.

You know, is all of this, You never really told him how many amps his clutch should draw.
 

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