Small Engines (Lawn Mowers, etc.): John Deere PTO issue, center bolt, issue question

Question
QUESTION: I have a JD 322 garden tractor, 18hp 3cyl liq. cooled Yanmar engine, with a front PTO problem. The front PTO (deck & snowblower drive) recently started acting up with intermittent trouble when trying to engage. Now it will not engage at all, I flip the switch and the dash indicator light comes on but nothing engages. Does this immediately mean a new front PTO assy or is there something in between? If it is the PTO, what is the proper way to remove the center bolt which appears to attach to the crankshaft (how to hold it from turning w/o damage)?

Thanks in advance, sure appreciate any help you can offer.

ANSWER: Hello Dave:

Check the Ground Wire for the PTO. Usually the Ground Becomes Corroded and Does Not Make a Good Connection and you Lose the Ground to the PTO. If you have an Ohmmeter, Disconnect the Wiring Harness from the Front of the Clutch and Check the Resistance of the Clutch. You should have around 4 or 5 OHMs. If at or near Zero, the Coil has Shorted. An Impact Wrench (Electric or Air) is the Best Way to Remove the Crankshaft Center Bolt to Remove the PTO from the Crankshaft. You can View a Breakdown/IPL of the Mower at this Site Addy, http://jdpc.deere.com/jdpc/servlet/com.deere.u90490.partscatalog.view.servlets.H and Enter the Model Numbers and Click Find. Then Select the Sectional File. Then Select the Section of the Mower you Wish to View Online. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 9pm EST (US). My New Day Starts then. Thanks.

Respectfully

John

---------- FOLLOW-UP ----------

QUESTION: Thanks Don, unfortunately I am more confused now... I checked the continuity of the PTO and it read 4.0 ohms so sounds OK. Also checked the switch side of the plug and it switches from 0V to 11.9V so appears to be getting power to the PTO fine. There is just the two prong plug from the PTO so I could not find a specific ground wire. Checked and cleaned the main engine ground (3 wires on it) but no difference. Tried a jumper from the battery to the PTO plug but still could not get it to engage. Any guesses? Could it be the brake safety switch involved here?

Also, a separate question - how do I properly check the alternator on this tractor? Suspect a problem with it as the battery indicator light occasionally comes on dimly - battery is new, connections are clean/tight and the belt is tight.

Thanks again for any help! Dave.


ANSWER: Hello Again Dave:

The PTO has 2 Wires. 1 is a Hot and the Other is a Ground. Locate the Ground Wire and Attach Another wire to the Ground Wire and then to the Engine Block. Does the PTO Function Now? If Yes, then the Ground for the Harness needs to be Located and Cleaned. Cleaning the Harness Ground May Correct the Battery Light Indicator Also. With the Engine Running at Full Throttle, a Voltage Reading at the Battey should Read 12.8VDC or Higher if the Alternator and Regulator are Operating Correctly. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

---------- FOLLOW-UP ----------

QUESTION: PTO issue... located engine ground which included battery negative cable, ground from harness plus a chassis ground - cleaned all lugs plus the frame end of the chassis ground. No difference. Connected separate ground wire to PTO ground wire - still nothing. Jumpered battery across PTO connections and nothing. Convinced it must be the PTO except the resistance check is good.

Charging Issue - Measured 12.1V at the battery connections running at full throttle. Suspect alternator needs replacement.

Any other suggestions, input or conclusions would be most appreciated.

Answer
Hi Dave:

Change the Alternator First. Sometimes a PTO Requires 12.6 VDC to Activate the Electromagnet. Usually if the OHMs Check is 4 to 5 OHMs, the PTO Windings are Good and it Should Work. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 9pm EST (US). My New Day Starts then. Thanks.

Respectfully

John