Toro 4100-D service manual Procedure for Cutting Deck Gear Pump Flow Test

Procedure for Cutting Deck Gear Pump Flow Test

NOTE: Over a period of time, the gears and wear plates in the gear pump can wear. A worn pump will by--pass oil and make the pump less efficient. Eventually, enough oil loss will occur to cause the cutting deck motors to stall under heavy cutting conditions. Continued operation with a worn, inefficient pump can generate excessive heat and cause damage to the seals and other compo- nents in the hydraulic system.

1.Make sure hydraulic oil is at normal operating tem- perature by operating the machine for approximately 10 minutes. Make sure the hydraulic tank is full.

2.Park machine on a level surface 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.Locate deck manifold for gear pump section to be tested. Disconnect hydraulic hose at deck manifold port (P1) (Fig. 36).

4.Install tester with pressure gauges and flow meter in series with the the disconnected hose and hydraulic manifold port (P1).

5.Make sure the flow control valve on the tester is fully open.

6.After installing tester, start engine and run at idle speed. Check for hydraulic leakage and correct before proceeding with test.

IMPORTANT: Do not run engine at full speed during testing. At full engine speed, cutting deck gear pump output can exceed 15 GPM and cause tester damage.

7.Using a phototac, adjust engine speed to 2400 RPM. Do not engage the cutting deck.

IMPORTANT: Do not fully restrict oil flow through tester. In this test, the flow tester is positioned be- fore the relief valve. Pump damage can occur if the oil flow is fully restricted.

8.Watch pressure gauge carefully while slowly closing the flow control valve until 2000 PSI is obtained. Verify with a phototac that the engine speed is 2400 RPM.

9.For a normal pump, gear pump flow should be approximately 14 GPM. Shut off engine. Record test re- sults.

10.If measured flow is less than 12 GPM or if a pressure of 2000 PSI cannot be obtained, check for restriction in the pump intake line. If line is not restricted, remove gear pump and repair or replace as necessary.

11.Disconnect flow tester from hydraulic hose and man- ifold port. Reconnect hose to the manifold.

12.Repeat test for second pump section if required.

	TO OIL COOLER
RIGHT	1
FRONT
	3
	4
	2

Figure 36

1.	Center deck manifold	3.	LH wing deck manifold
2.	Hyd. hose to front P1	4.	Hyd. hose to side P1

Hydraulic System

Groundsmaster 4100--D Page 4 -- 47 Hydraulic System