Service Manual
Rev. AGroundsmaster 4100--D/4110--D Hydraulic SystemPage 4 -- 47
Procedurefor Rear Traction Circuit (RV) Relief Pres-
sure Test
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine under load for
approximately ten (10) minutes. Make sure the hydrau-
lic tank is full.
2. Parkmachine ona levelsurface with the cutting deck
lowered and off. Make sure engine is off and the parking
brake is engaged.
CAUTION
Prevent personal injury and/or damage to equip-
ment. Read all WARNINGS, CAUTIONS and Pre-
cautions for Hydraulic Testing at the beginning
of this section.
3. Measure and record traction circuit pressure redu-
cing valve (PR) pressure (see Traction Circuit Pressure
Reducing Valve (PR) Pressure Test in this section).
4. Connect a 1000 PSI (70 bar) pressure gauge to test
port on 4WD manifold under radiator. This is the same
pressuregaugeposition asused tomeasuretraction cir-
cuit pressure reducing valve (PR) pressure.
5. After installing pressure gauge, start engine and run
at idle speed. Check for hydraulic leakage at pressure
gauge location and correct before proceeding with test.
6. Move throttle so engine is running at high idle speed
(2870 RPM).
7. Operate the machine in Low speed (4WD) with the
cutting decklowered.Drive down a slope in a forward di-
rection, decrease pressure on the traction pedal and
monitor the pressure gauge. Pressure should increase
until the rear traction relief valve (RV) lifts. Record test
results.
8. Stop engine and record test results.
9. Relief (RV) pressure should be approximately 750
PSI (52 bar) and at least 100 PSI (7 bar) higher than
the traction circuit pressure reducing valve (PR)
pressure (e.g. if the pressure reducing valve (PR) pres-
sure is 650 PSI (45 bar), relief (RV) pressure should be
at least 750 (52 bar) but not much higher).
10.If specification is not met, clean or adjust relief valve
(RV) in 4WD control manifold. Relief valve (RV) is lo-
cated on the lower, front side of the 4WD control man-
ifold (Fig. 35). See AdjustControl Manifold Relief Valves
in the Adjustments section of this chapter for the valve
adjustment procedure. Recheck relief valve (RV) pres-
sure setting after adjustment and readjust as needed.
11.When testing is completed, disconnect pressure
gauge from manifold test port.
1. 4WD control manifold 2. Pressure test port
Figure 34
1
2
1. Manifold: front side 2. Relief valve (RV)
Figure 35
1
2
Hydraulic
System