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Help on p218 voltage regulator

7429 Views 3 Replies 3 Participants Last post by  SWIGIN
New Years Day and my p218 came to life after long hours with the paint and starter issues etc.Now when it starts the battery light stays on and the oil light WON'T come on,I have seen here how to check the VR but don't recall the procedure,I have checked the outside post's on the vr and they are 12+ volts on each side hooked up.Anybody know the right way to check it.The p218 really sounds good and is really quiet.Thanks in advance
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There are three terminals on the voltage regulator. The outer two are from the stator and that is where the AC (not DC) voltage connects. The middle terminal is the output for DC (not AC) voltage to the battery.

With the tractor off, key off, disconnect the wire from the middle terminal. Set your multi-meter to read DC volts. Start the tractor and run at full throttle. Touch the black probe from your meter to a known good ground point. I prefer the engine block. Then and only then, touch the red probe from your meter to the bare middle terminal. Output reading should be 13.5 to 14.5 Volts DC.

If the reading is less than indicated:

With tractor off, key off, make sure the middle terminal wire is connected. Disconnect both outer stator leads from the voltage regulator. Set your multi-meter to read AC volts. Connect one probe into one of the stator leads and the other probe to the remaining stator lead. It does not matter which lead is connected to which probe. Start the tractor and run at full throttle. The meter should indicate at least 28 volts AC to 41 volts AC (Spec A) or 57 volts AC (Spec C).

Tractor off, key off, set multi-meter to check resistance. Check each stator lead independently for continuity to ground. There should be none measured. If continuity is measured, there's a short in the stator and it will need to be replaced.

Tractor off, key off, set multi-meter to check resistance. Check the resistance between the two stator leads. Resistance should be 0.06—0.10 ohms (Spec A) or 0.10—0.19 ohms (Spec B). If resistance measured is outside these specs, the stator should be replaced.

If all tests but the first one check, the voltage regulator should be replaced.

Hope that helps.
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Thanks STASH,will get to this tomorrow.
Wow Stash, that is some GREAT info!

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