markbrown47

Does anyone have the testing procedures for testing the stator and the regulator/retifier on this engine. And also what are the specs? This motor is on a John Deere L 111.

Thanks,
Mark Brown

MikeWitt

I have the same 20hp intek v twin. The manual shows to test the output of the alternator with the AC volts test by checking across the yellow connector with two black wires coming from under the engine cover. The wires change to two yellow wires at the connector and go to the regulator.

You can recognize the regulator as a square metal shaped block with green epoxy square held on by two screws, and three wires coming from it - two yellow and one red.

The connector we're concerned about has black wires on the engine side of the connector and yellow wires on the other (regulator) side of the connector.

Your meter should be set to read voltage - over 30volts (set it on the 100 volt setting) - the red lead plugged into the V/ohm receptacle and the black to the com

According to the manual, separate the afore mentioned yellow connector and connect your ac volt meter to the pins in the engine side of it - you're reading across the stator (it doesn't matter which lead from the meter goes to which pin - if the reading is negative you've just got the leads switched - just read the absolute value) - black lead to one pin, and red lead to the other. Start the engine, warm it up, set the rpms to 3600, and read the meter.

The reading should be 28volts ac minimum for the 10 or 13 amp alternator, or 30volts ac minimum for the 16 amp alternator. If the readings are incorrect they say replace the stator. If you don't have a way to check the rpms you should be fine just running at fairly high engine speed. The alternator should generate voltage to some extent at all speeds. Be sure to shut down the engine before removing leads and reconnecting the wires after completing the test. If your stator checks out good then you need to measure the output of the regulator.

To measure the amperage output of the regulator it's a little more complicated. You must change the leads on your meter to measure amperage - if you measure incorrectly this can blow your meter so attention to detail here is important! The black lead on your meter still is plugged into the com receptacle, but the red lead moves to the AMPs receptacle. Set the dial on your meter to measure 10 amps. You'll be measuring inline with this test.

Remember the description of the regulator above? find the read wire coming from the regulator (between the two yellow wires) and disconnect it at the first red connector - it has two small ears on the connector that have to be spread out slightly to enable the connector to come apart.

Connect the black lead of your meter to the batteries positive terminal. Connect the red lead from the meter to the red wire coming from the regulator - the regulator side of the red connector. Start the engine, warm it up, set rpms to 3600, and read the meter. The reading should be 2 to 4 amps. Power off the engine, and reconnect everything. If the stator passed the first test, and you get the required 2 to 4 amps when checking the regulator on this test, then the problem is down stream - loose connector, maybe bad switch... If you don't get the required 2 to 4 amps, then the problems with the regulator. Actually you should probably just check the DC amps coming from the regulator first before checking the stator, then you'll know if there's an issue with your charging system at all. That way if the regulator output tests good you know the stator is good too.

Most important! turn off your meter and set the leads on your meter back to V/ohm for the red lead and COM for the black lead otherwise the first time you go to read voltage or ohms you'll blow the meter.

I've given the instructions as listed in the manual. Good luck