z445 possible electrical issue

[z445]

Mower: 2013 JD z445 Zero Turn

The battery is 1 year old, I have been mowing flawlessly every week since Mid April...

The issue started the other day. Started ran and mowed just fine. When I finished, I parked it to cool down while I did some other things around the property.
Go back an hour later to move it back to the shed and turn key to start, nothing.. no click, no turning of the starter, no noise of any kind.

I checked all of the fuses/battery connections and all were good. I attached a Battery charger/Starter and set it to full charge and let it sit a min or two.
I attempted to start and starter turned the motor slowly but enough that it started. So I was able to move it in the shed for the night.

I went back out yesterday and attempted to start, turn key and again nothing, no click, no starter turning, no start.
Attached the Battery Charger/Starter, turned it on a full charge and let it sit for a few mins and again attempted to start, turn the key and motor turned over slowly enough to start.

I then pulled the mower out of the shed and pulled PTO switch to activate blades. When I did that the motor immediately sputtered and then died.
Attached Battery Charger, turned to full charge and got the engine to start again. Pulled the PTO switch and again the engine sputtered and I immediately shut the PTO switch off and the motor quit sputtering and ran normally.

It seems I have a severe power draw, Battery Charger/Starter has to be on full charge for it to be able to turn just fast enough for it to start and when I activate the PTO for the blades the engine will die.
I'm thinking the PTO clutch is bad(short to ground?)

any thoughts? advice, ideas welcomed

Thanks

 

[mercdv]

Before assuming something else is bad, I'd check to see if the battery will actually hold a charge. Do a full charge on the battery and measure the volts when it has completed a full charge cycle, then measure the volts with the mower running. If all that checks out, then I would start looking for some sort of drain. Sometimes batteries develop internal problems from vibrations and other various things causing a cell to die or an internal short. My original JD battery only lasted 8 months before it developed a problem and wouldn't hold a charge. I replaced it with an AGM style battery and it has been rock solid.

 

[Richard001]

Before assuming something else is bad, I'd check to see if the battery will actually hold a charge. Do a full charge on the battery and measure the volts when it has completed a full charge cycle, then measure the volts with the mower running. If all that checks out, then I would start looking for some sort of drain. Sometimes batteries develop internal problems from vibrations and other various things causing a cell to die or an internal short. My original JD battery only lasted 8 months before it developed a problem and wouldn't hold a charge. I replaced it with an AGM style battery and it has been rock solid.

What mercdv said, but just to add, after charging the battery, if your charger is low current, like less than 5 amps, leave the charger on for at least 10 to 12 hours. The disconnect the charger and wait several hours, as there is always a residual extra charge on the battery from the charger before you measure the battery voltage. Here is some info on lead-acid battery's:

A fully charged cell at 80 degrees F would show a specific gravity of 1.265. If all six cells are fully charged, an accurate digital voltmeter reading of battery voltage would show 12.68 volts.

Specific gravity for a 50 percent discharged cell would drop to 1.19 and battery voltage would fall to 12.24.

When specific gravity reaches 1.12, the cell is fully discharged and battery voltage falls to 11.89 volts, assuming the specific gravity is the same in all six cells.

If your battery is not a sealed type, check the water level.

After you start the engine, measure the voltage on the battery terminals. A good voltage regulator will put about 14.5 volts on the battery when the engine is running. If you are not getting this, then you have an alternator or regulator problem.

Richard

 

[Richard001]

OH, and welcome to TBN

 

[Kish318420]

Voltage Regulators put out a charge voltage between 14.3 and 14.8 VDC

 

[Richard001]

Voltage Regulators put out a charge voltage between 14.3 and 14.8 VDC

Thanks for confirming what I posted.

Richard

 

[z445]

I pulled Battery and tested it:
Removed from mower: 10.51DCV

After 6 hours charge: 10.86 DCV

So I will replace the battery tomorrow and report back

 

[Wagtail]

Just remember that when it comes to starting the engine, it is the battery's Amps that do the work... your battery charger will (should) be fairly quick to change the battery's Voltage but it will take a lot longer to increase the Amperage required. (Your 6 hour charge will have accomplished the Amp charge)

Once started, the amperage required drops away significantly and the engine/mower runs fine.

 

[z445]

Replaced Battery. Mower starts and runs normally.
Tested while running and it shows the system is getting 14.8DCV



Thanks for all the help:thumbsup:

 

[mercdv]

Replaced Battery. Mower starts and runs normally.
Tested while running and it shows the system is getting 14.8DCV



Thanks for all the help:thumbsup:

Glad it is all working now but hate you had to buy a new battery. I always cringe when I go in to buy one because I know I'm putting money into something that is just going to eventually die again.