Kubota RTV1140CPX, Workshop Manual

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TRANSMISSION
RTV1140CPX, WSM
2-M11
[C] HST Oil Flow
(A) Neutral
The oil that is drawn by the charge pump (20) from the transmission case (15) through the oil filter cartridge (18)
and charge relief valve (17) into the HST hydraulic circuit and regulator valve (2). Surplus flow is returned from the
charge relief valve (17) to the HST housing (6) and finally into the transmission case (15).
When the pedal (1) is released (neutral position), the regulator spool (3) is also at the neutral position. The pump
variable swash plate is interlocked with the servo piston (4), will not tilt.
In this way, the HST pump (19) keeps rotating but the pump piston is stationary as no oil is being fed from the
HST pump (19). Until oil is fed back from the HST pump (19), the cylinder assembly of the stationary motor (13) and
assist motor (9) are halted which keeps the output shaft from turning.
9Y1210293TRM0011US0
(1) Pedal
(2) Regulator Valve Assembly
(3) Regulator Spool
(4) Servo Piston
(5) Cylinder Block
(6) HST Housing
(7) Control Piston
(8) Variable Swashplate
(Assist Motor)
(9) Cylinder Block (Assist Motor)
(10) Check and High Pressure
Relief Valve (Forward)
(11) Unload Valve
(12) Check and High Pressure
Relief Valve
(13) Cylinder Block
(Stationary Motor)
(14) Anti-cavitation Valve
(15) Transmission Case
(16) Output Shaft
(17) Charge Relief Valve
(18) Oil Filter Cartridge (Suction)
(19) Variable Swashplate
(HST Pump)
(20) Charge Pump
(21) Input Shaft
(22) Oil Filter Cartridge
(23) Orifice
a: To HST Housing
KiSC issued 05, 2014 A