Toro Reelmaster 5510 Series, Service Manual

Page: 228 / 662

Testing the Traction Circuit–Piston Pump/Hydrostat Flow and
Relief Pressure (5610-D)
g216148
Figure 120
The hydrostat flow test is the third in a series of tests recommended to determine
the traction circuit performance. This test compares fluid flow at No Load with
fluid flow Under Load. A drop in flow under load of more than 12% indicates
an internal leak or malfunctioning relief valve in the piston pump/hydrostat. A
worn hydrostat or malfunctioning relief valve is less efficient. Eventually, enough
fluid bypass will cause the unit to stall under heavy load conditions. Continued
operation can generate excessive heat, cause damage to seals and other
components in the hydraulic system, and affect overall machine performance.
Special Equipment Required:
•
Pressure gauge
•
Flow meter with pressure gauge that has at least a 114 L/minute (30
gallons/minute) capacity
Test Procedure
1. Warm oil after test equipment is connected to prevent technician from
working on a hot machine—applicable to tests when possible (any test that
requires an open un-pluged/capped line (case drain tests) would not apply
and oil should be warmed before disconnecting the lines).
Hydraulic System: Testing the Hydraulic System Page 6–110 Reelmaster ® 5410/5510/5610 Series
15216SL Rev C