I have a 2004 Toro Z Master zero turn mower. Model 74162 S# 240000689 18 Hp Kohler 560 hours After about 5 minutes of cutting grass the Blades stop turning. It seems like the PTO disengages. If I let it cool off it will engage again for at least 5 minutes of cutting. I replaced the PTO switch thinking it may be defective but this didn't help. I was told that the battery could be the problem since the clutch is electric the battery might not have enough power even if it is strong enough to start the mower. I thought about trying that before having a new clutch put on. Have you ever heard of this or have any ideas what it could be.