Export thread

Hello I have a CC zero turn and the pto just shuts off while mowing, If I shut off the motor it won't restart the battery is dead. has new battery and the mower can set for weeks and starts right up. battery only goes dead when pto acts up. Any ideas. Thanks Jon

Sounds like you could have a safety switch issue. Check and make sure your seat switch has a good connection.

Thanks would this make my battery go dead ? When it acts up the battery goes dead.

Jons said:

Hello I have a CC zero turn and the pto just shuts off while mowing, If I shut off the motor it won't restart the battery is dead. has new battery and the mower can set for weeks and starts right up. battery only goes dead when pto acts up. Any ideas. Thanks Jon

Click to expand...

WELCOME to LMF...
Are you saying that ... When the battery is so near dead while mowing, the PTO clutch will disengage and then after shutting off the engine, the battery is (still) so discharged that it will not restart the engine.... ?

If that's what is happening, That would be normal... The PTO clutch needs full voltage to remain engaged... If the charging circuit is not keeping the battery Above 12 volts with the engine running, the PTO clutch will drain the battery down to the point it will disengage, at that point there will not be enough left in the battery to start the engine.

Check the charging circuit out... If you allow the PTO to run with low voltage it will burn out the clutch... :smile:KennyV

Hi Thanks, when I mow sometimes after 30 min of mowing if I stop the pto blades to pickup something on the ground the pto won't start back up. Let mower sit for half hour turned off, then restart engine which starts fine lots of battery power and pto engages fine. Lately the pto just stops and the battery is dead. It seems like when pto stops it will drain battery in few seconds. If I can get thru mowing and park unit restarts one week later perfect. Thanks again.

Check voltage at the battery, you have something not right with the charging system...
Voltage should be slightly above 12 volts with engine OFF... and above 13 volts with engine running AND PTO on...
Could be a loose OR corroded connection... :smile:KennyV

Thanks again will let you know what I find. (with your help) Jon

Put battery charger on mower for three hours, then mowed rest of 3 acres ran fine no pto disengagement. Just went and checked battery after sitting for few hours, Battery has 12.2 volts, started up, reved up and it stayed at 12.2 so no charging. Where should I look for no charging. Thanks again. Jon

Now you are on the track of the real problem... not charging.
Check for a fuse or fuseable link ...
also check the voltage regulator...
remember all connections have to be good & clean...:smile:KennyV

Ok fixed, had a bad stator, no charging to battery. Thanks for all the help, KennyV
Jon :smile:

Spoke too soon, took apart and stator was fine. Found problem, all the magnets had came off. Nothing damaged just all the magnets off. Put on new flywheel and charging fine. Thanks for all the quick help. Jon

Wow that is a bit scary.

Glad you found it.

I wonder if this is common.

What model is this ZTR?

It's a year 2000, model 3660 with 25 H.P. Kohler. My guy that helped me, said he never saw this and he works in a lawn & garden store for the last twenty years.

I am having the same problem with my brother in laws. He has gone through three batteries and as ask me to take a look at it. It has a 22HP B&S and I have checked the battery and it has 12.5 volts. When the motor was running it still have 12.5 volts at the battery. He purchased a new alternator and we placed it on the mower and now it has 12.6 to 12.7 volts. I tested the capacitor against ground fault and it passed. What else could cause the electric PTO to drain the battery while in use?

The voltage reading you are getting are still too low. Either the alternator is bad, a bad voltage regulator, or are not getting battery voltage to the voltage regulator.

Also if the battery is going bad, and the voltage drops below 12 V it will shut down the regulator.

How do I test the alternator with my test meter? The style I have is the one wire. Is there a way to find out what it is sending to the battery?