[Charlie-141 FE]

I have searched and could not find a previous thread on this but I'm sure I have seen one, I mowed for the first time this year with my 1810, mowed for about 2 minutes and the pto disenguaged. re started and ran for a minute then disengaged. Then it would not restart, waited a few minutes then it started again. Long story short it works intermittenly. Anyone know of a particular reason for this? The PO has bypassed the reverse toggle switch that is activated when putting the tractor in reverse, i pulled the conector apart and the mower deck stopped, I am assuming that switch is in line with the PTO but am not sure what other components are. Is there a wireing diagram somewhere? Thanks