Toro Groundsmaster 3280-D Service Manual page 136

Implement Relief Pressure Test (Using Pressure Gauge) (Machine
Serial Numbers below 316000000) (continued)
Hydraulic System: Testing the Hydraulic System
Note: If the implement relief pressure is 4,820 to 6,900 kPa (700 to 1,000
psi) and a steering or lift problem occurs, inspect for a problem unrelated to
the hydraulic circuit (e.g., binding steering or lift system components, debris
build-up on/under the cutting deck). Check and repair other items before
continuing with hydraulic tests.
4. If the implement relief pressure is below 4,820 kPa (700 psi), adjust the
implement relief valve in the transmission by adding the required amount
of shims from the shim pack; refer to Implement Relief Valve in the
Sauer-Danfoss (Sundstrand) 15 Series Service Manual at the end of this
chapter.
Note: For every 0.254 mm (0.010 inch) of shim thickness, there is an
approximate 340 kPa (50 psi) change in implement relief pressure.
If adding shims to the relief valve does not increase pressure, inspect the
condition of the charge pump gerotor and internal housing; refer to Charge
Pump Service in the Sauer-Danfoss (Sundstrand) 15 Series Service Manual
at the end of this chapter.
If the charge pump is in good condition (no scoring, scratches, or excessive
wear), the general condition of the transmission's piston pump and piston
motor might be suspected of wear and inefficiency. A lack of minimum
implement relief pressure could be due to the charge pump having to direct
all flow to the main traction circuit (piston pump and piston motor).
5. Disconnect pressure gauge from the transmission. Install pipe plug back in
the transmission. Check hydraulic-fluid level in reservoir (front axle).
Page 5–52 Groundsmaster ® 3280-D/3320
05138SL Rev B