Usage:
928G (6XR, 7SR) Wheel Loaders IT28G (8CR, 9AR) Intergrated Toolcarriers
Reference: SENR1223, 928G and IT28G Brakes and Fan Specifications, Systems Operations, Testing and Adjusting, Page 37.
The following information is the correct procedure for checking the Fan Speed and Fan Motor Pressure.
NOTE: 1 means the part is a component of 4C-4892 Fittings Group-ORFS Adapter. This is a General Dealer Tool. Check the group for individual item quantities.
NOTE: 2 means the part is a component of 9U-7400 Multitach II Group. This is a Diagnostic Dealer Tool.
NOTE: 3 means the part is a component of 1U-5796 Differential Pressure Gauge Group. This is a Diagnostic Dealer Tool.
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Refer to Warning on the first page of Testing And Adjusting Section.
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Before testing the machine:
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- * Move the machine to a level area.
- * Make sure the engine is OFF.
- * Engage the Parking Brake.
- * Move the Transmission Lever into the Neutral Position.
- * Inspect all hoses, connectors, and components that apply to the system for damage.
- * Relieve all the system pressure.
- * Move the machine to a level area.
Illustration 1. Elbow and Hose Connection.
Pressure Test Hose Assembly
1. Move the hose guard (1) to the right to improve access.
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Before disconnecting any hydraulic hoses, release the hydraulic pressure in the hydraulic system by pushing and pulling the hydraulic control lever several times.
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2. Disconnect the hose assemblies (2) and (4) from the elbows (3) and (5).
3. Install one 7X-0871 Tee (6) between each hose assembly and elbow.
4. Install a 5P-8869 Connector (7) to the ports in each tee.
5. Attach one 6V-3966 Nipple Assembly (8) to each connector.
6. Attach one end of the 6V-4143 Coupler Assembly (9) and 1U-5755 Hose Assembly (10) to the nipple assembly installed between (4) and (5).
Attach the other end of the coupler assembly and hose assembly to 8T-0855 [0-4000.0 kPa (0-580 psi)] Pressure Gauge (11).
7. Attach one end of the second coupler and hose assembly to 8T-0860 Pressure Gauge [0-40 000.0 kPa (0-5800 psi)] (12).
Attach the other end of the hose and coupler assembly to the nipple assembly between (2) and (3).
Illustration 2.
Illustration 3.
Installing the 9U-7400 Multitach
Look through the grill to see if 1U-6605 Reflective Tape (13) is on a fan blade like (14). If reflective tape is on the fan blade then the fan speed can be checked with a hand held photo tachometer with the grill on the machine. Go to Step 4 below. If no reflective tape is on the fan blade, go to Step 1 below.
1. Remove the grill assembly (15). It is held in place by four bolts and four washers. It weighs only 16.8 Kg (37 lb).
2. Attach 1U-6605 Reflective Tape to the fan motor as at (16).
3 . Install the grill assembly. Torque the bolts to 55 ± 10 N·m (40 ± 7 lb ft).
4. Install the 9U-7400 Multitach II Group (17) to the grill as at (18).
Pressure and RPM Test
1. Start the engine and run at low idle.
NOTE: To obtain accurate pressure readings, the hydraulic oil must be at normal operating temperature.
2. Slowly increase the idle speed until the machine is at high idle. Read the pressure gauge in the bottom (inlet) line. The pressure should be 15 850.0 ± 345.0 kPa (2 300 ± 50 psi). Read the pressure in the top (outlet) line. The pressure should be 515.0 ± 170.0 kPa (75 ± 25 psi).
Illustration 4. Fan Pump.
3. If the pressure in the inlet line is not to specifications, check the pressure at the pump. Remove 8T-0860 Pressure Gauge from the inlet line. Attach the pressure gauge to to Pressure Tap (19) on the pump.
4. Start the engine. Slowly increase the RPM to high idle. Look at the pressure gauge. The pressure should be 15 850.0 ± 345.0 kPa (2 300 ± 50 psi).
5. If the pressure at the pump is not to specification, check the engine RPM setting, go to step 18.
6. If the engine RPM is incorrect, set the RPM to specifications. Repeat Step 4.
7. If the engine RPM is correct, replace 143-1357 Valve Group-Unload (cartridge type relief valve) (20) with a known good relief valve.
8. Repeat Step 4. If the pressure is not to specification the pump will have to be replaced. If the pressure is correct, go to step 16 below.
9. If the pressure in the outlet line is not to specification, replace the cartridge type relief valve in the fan motor.
10. Return the engine to low idle. Stop the engine.
Illustration 5. Fan Motor Relief Valve.
11. Move the attachment control lever(s) to all positions to relieve the system pressure. Apply the service brake approximately 15 times to relieve pressure. Remove the four bolts and the grill assembly.
12. Remove and replace 152-1957 Relief Valve (21) in the fan drive motor with a known good relief valve.
13. Reinstall the grill assembly. Torque the four bolts to 55 ± 10 N·m (40 ± 7 lb ft).
14. Put 8T-0860 Pressure Gauge back onto the fan motor inlet line.
15. Repeat Steps 14 and 15. If the pressure now correct, procede to Step 16.
16. Disconnect the pressure gauge, fittings, and hose assemblies from between the hose assemblies (2) and (4) and elbows (3) and (5).
17. Reconnect hose assembly (2) and elbow (3), and hose assembly (4) and elbow (5).
18. Start the engine. Increase the idle until the machine is at high idle and normal operating temperature.
19. Record the fan speed showing on the multitach. The fan speed should be 1350 ± 100 Rpm.