Electrical charging pto issue JD 145 automatic

[jrv8984]

Few weeks ago the mower deck wouldn't engage, but I was having a hard time starting the mower and was having to jump it. Got a new battery, and noticed that the solenoid nut holding on the starter cable was missing. Fixed that, but the wife was mowing the other day and the pto just stopped again and wouldn't start. Shut mower off and had to jump it. Got the mower running disconnected the battery and it kept running, so the alternator should be doing its job. So I'm guessing that the pto is drawing down the battery. Anybody have any ideas what might be going on? Thanks

 

[atsah]

Sounds like the PTO switch is shorted.

 

[RandyT]

Unless that engine has a fuel solenoid on the bottom of the carb, no electric power is required to run the engine. I suspect that the charging system isn't working. It can be checked with a volt meter across the battery terminals as see what the voltage is. Less than 13 volts would say it isn't working. Also even with the fuel solenoid it only needs 9 volts to operate whereas the electric clutch needs closer to 12 so it will shut down before the voltage drops enough to kill the fuel solenoid causing the engine to die.

 

[atsah]

Looks like he removed the battery cable while running and it stays running which indicates the charging system is working.

 

[jrv8984]

I'm not a small engine guy. But if the charging system isn't working there would be no electricity for the spark plugs when the batteries disconnected. Or am I missing something that's different with small engines?

 

[Dave M7040]

I'm not a small engine guy. But if the charging system isn't working there would be no electricity for the spark plugs when the batteries disconnected. Or am I missing something that's different with small engines?

Engine is likely running on a magneto for spark so battery is only for starting, engaging electrical pto clutch and lights. You really do not have an alternator but a dynamo. It uses permanent magnets for the magnetic field rather than coils of wire as an alternator has.

A $10 multimeter will tell you a lot about what is going on.

Dave M7040

 

[RandyT]

I'm not a small engine guy. But if the charging system isn't working there would be no electricity for the spark plugs when the batteries disconnected. Or am I missing something that's different with small engines?

Except in a few engines like some of the kawasaki's and a few Kohlers the ignition system is self powered by a magnet on the outside of the flywheel passing an magneto that generates spark. the charging system consist of magnets on the underside of the flywheel, running next to a stator that may or may not go to a regulator/rectifier, and then to the battery to recharge it, and run other things like the pto clutch. Posting the model number information from the engine will help to narrow down the troubleshooting of the charging system.

 

[jrv8984]

Model 441777
Type 0116 E1
Code 051128YG

 

[tomplum]

Briggs Portal shows that you have the dual circuit alternator, so you would follow the test procedures for that style. But likely your PTO is drawing too many AMPS. The clutches tend to stay running until about 10 Volts or less and as others have said eventually the fuel solenoid will close and there you are, dead in the lawn. So, you want to know your new battery is up for the task. It should really be 250 CCA or more and if so charge and have it load tested. You can then determine if your charge system is working and how many AMPS your clutch is drawing. As Randy said, if you alternator is charging , you should have 13-14 VDC across your battery terminals at wide open throttle. Engage the clutch and if it pulls if down considerably that would be another hint...

 

[RandyT]

Dual circuit charging isn't normally used with the electric clutch mowers. I suspect he had the 10-16 amp charging system with the square regulator/rectifier mounted on the what would be the left side cylinder if sitting on the seat. Two wires with a yellow connector going into the regulator with a single wire with a barrel type connector with battery voltage.