5/9/2018 10:05 AM
I have a Toro 4500D 30856-2700000131 serial number that has a random PTO shutting off and then turning back on magically usually within a few seconds. This machine was purchased used by my club with 2887 hrs Jan 2017. From my understanding it has always had this problem. Here is some history of what has been done.
Jan 2017 2887 hrs -- hyd fluid changed to Bio Syn Extra
Jul 2017 3134 hrs -- mow solenoids swapped out with spares
Jul 2017 3200 hrs -- drained hyd fluid added Napa AW46 hyd oil and 48oz Lucas trans fix
Sept 2017 3391 hrs -- replaced proximity switch under lift lower handle
Sept 2017 3396 hrs-- swapped main control module board with working unit in fleet
Oct 2017. 3503 hrs -- machine to local Toro vendor replaced ignition switch PTO rocker switch check all wiring - can not replicate problem
Nov 2017 mechanic retired I inherited problem
Dec 2017 replaced seal in rear end letting hyd oil into rear end
Mar 2018 check and bypass each of the following with no change--seat switch, PTO relays, ohms check on both solenoids good, high low 2wd 4wd switch, circuit board diode swapped with working unit, both front deck position sensors. Swapped ramp up module. Checked center PTO switch on lift lower handle. Park brake switch
95% of time the blades work when they do work the PTO output light on the control module is bright sending power to the ramp up module then the blades engage. When the blades do not turn on the PTO light is very dim and flickers sending no power to the ramp up module. At this time you can hear the center PTO relay clicking. The machine can sit with PTO on blades not turning PTO light dim/ flickering, by doing nothing all of a sudden blades will start PTO light is full lit.
Any help is appreciated