I-37
35 Series 4WD, Model - 3535, 4035, 4535 and 5035 SM June’08
Hydraulics
19. PTO CONTROL VALVE
a. Specification of PTO Control Valve
MAKE – ARON
Fluid Temperature – - 40ºC to 100ºC
Pressure – 16 - 18 bar
b. General Description
This series of tractors is equipped with Hydraulically
operated wet PTO clutch which is controlled by PTO
control valve mounted on RH side of tractor below
platform. Hydraulic power is taken from the return
line of steering unit. The PTO control valve provides
actuation pressure of 16-18 Bar in ‘ON’ condition,
also it provides lubrication flow to ‘WET PTO Clutch’,
synchroniser and spline shaft.
c. Theory of Operation (Refer Circuit I-4)
When the PTO ON/OFF button is in ‘OFF’ position
all the oil enters through ‘P’ port and leaves through
‘L’ port for the lubrication of ‘Wet PTO Clutch’,
synchroniser and spline shaft. Now, when it is put
to ‘ON’ position solenoid gets energised and shifts
the spool. This diverts part of oil to the PTO clutch
cylinder and hence PTO gets engaged.
d. Removal & Refitment of PTO Control Valve
1. Drain transmission oil completely from the
transmission housing by loosening drain plug.
2. Remove PTO pipes connectors and bolts to
separate valve.
3. Remove PTO control valve.
Service Recommendation:
It is not recommended to repair PTO Control Valve.
PTO Control Valve should be completely replaced,
if internal problem is suspected.