Toro Groundsmaster 7210, Service Manual

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Testing the Traction System Operation
Because the traction system of the Groundsmaster 7210 machine uses 2
different circuits, it is difficult to identify which circuit is causing a problem and
what hydraulic tests should be performed. Use the following operation tests and
suggestions before you perform the hydraulic tests described in this section.
1. If the machine does not track in a straight line, look for a problem with the
components that affect the weaker traction side of the machine. During
operation, the machine will steer toward the weaker side of the traction
system. Because the swash plate of the piston pump is controlled by the
traction control lever movement, if 1 lever rotates its swash plate more than
the other lever, the machine will not track in a straight line.
2. Drive the machine up a moderate incline, shut off the engine, place
the traction-control levers in the N
EUTRAL LOCK
position and allow the
transmission to hold the machine in place (the parking brake is not applied).
The machine should remain stationary on the incline or drift slowly backwards
in a straight line. If 1 of the traction circuits of the transmission is damaged,
the machine will roll backwards toward the weaker traction circuit.
3. The wheel speed should be the same on the 2 rear wheels. Ensure that the
hydraulic fluid is at normal operating temperature. With the machine raised
off the ground and correctly supported with jack stands, have an operator
in the seat move the traction-control levers to the full forward speed. Use a
phototac to check the rotational speed of the 2 rear wheels. The wheel speed
should be 190 to 200 rpm for both rear wheels.
4. If any of these operation tests suggest a traction system problem, check the
following before you perform the hydraulic tests.
A. The parking brake is dragging.
B. The traction-control lever is not adjusted correctly.
C. The transmission bypass valve is not seated.
D. Check the hydraulic-fluid level in the hydraulic tank to ensure that the
fluid level is correct.
Groundsmaster 7210 Page 4–33 Hydraulic System: Testing the Hydraulic System
16222SL Rev C