318 battery light on

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318 battery light on

T Hake My 318 tractors battery light stays on all the time. Can someone tell how and where to check the charging system at? I replaced the battey thinking the battery was bad. This did not work though. Also the electric clutch does not engage all the time. Have to jurk it in to revese to make it come on. Any ideas for the problems that I am having?
Dave T - Sounds like it could be the voltage regulator. It's rectangular and located on the right side of the engine, in the black metal shroud around the engine. There are three wires connected to it. The outer two wires come from the stator. The middle wire is the voltage out to the battery.

First, make sure all connections at the battery, ignition switch, pto switch, starter, and main ground are clean and free of corrosion. It's a pain, but too much corrosion at any of these connections can cause problems.

With the tractor off, disconnect the middle wire from the voltage regulator. Start the tractor and run at fast idle. With a voltmeter, touch the black probe to a known frame ground on the tractor, THEN AND ONLY THEN, the red probe to the middle exposed terminal. You should get a reading of 13 to 14.5 volts DC. My guess is it's less than 12 volts.

To make sure the problem is the voltage regulator and not the stator, shut the tractor off. Now replace the middle wire. Remove the two outer wires from the voltage regulator. Attach one probe of the volt meter to one lead and the other probe to the remaining lead. This time, you'll be checking for AC voltage, not DC voltage. Start the tractor and run at fast idle. You should get a reading of at least 28 volts AC up to 57 volts AC. If that checks out, replace the voltage regulator. If not, most likely it's the stator. Good luck - Dave

T Hake Thanks Dave
Voltage regulator was the problem with the battery light. Replaced and works good know.
I found a plug-in ground connector on the back side of the battery that had a lot of corrosion on it so I respliced the wire.
Had good voltage going to the regulator from the stator.
The PTO clutch still does not come on every time the switch is turned on. Lifted up off of the seat when the switch was on and the pto light went out. You can throttle down the engine some and turn on the switch and the pto will come on and the throttle up the engine. Also I can start to pull it back into reverse and it will come on with the switch on.

Mike I measured the DC V across my battery terminals and there was little, if any, change with or without the engine running. Measured about 12.35V. I now want to test my voltage regulator, but am a little confused. Mine is a flat rectangular box as described above, but my wires are in a different orientation. I have an Onan if that matters. Two wires (b&c) go off to something (Stator?) and one wire (a) joins a close-by wiring harness. The two wires that are together are in the middle of this long block, stacked one about the other. The 3rd is off to one side.
| -(b) |
| -(a) -(c) |
Can someone tell me how to test this?

mike My diagram above did not display as I submitted. As you are looking at the terminals, "A" is on one side with "B" & "C" stacked in the middle. there is nothing on the right side.
Sorry if this caused confusion.

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