Mower deck Zero Turn PTO Problem

I have used it twice this year. My 12 plus year old Zero Turn mows fine for an hour then the PTO disengages and will not engage. I put it away and tried later with no success. I bought a new PTO shift and the PTO started without a hitch. Mowed for about an hour and the smae thing happpeded again. and now it won't engage again. ANY SUGGESTIONS

First check the ground wire. Check the charging make sure it is. Then check the clutch for the ohms depends on what clutch you have like a 3.5 and so on depends on the ohms reading and failure point of the clutch. If it is burning up the pto switch more likely the clutch or charging issue and sometimes both. Need to know engine numbers and model number of your unit to tell more about what the problem is and how to help.

Check the battery voltage before you turn the mower on the again after you turn the mower on and the hard bit with the blades turned on
Let us know what you find.
Should be
better than 12 V
Better than 13 V
better than 13 V