deceleration

Figure 5.36. Hydraulic fluid flow during mast lifting

1. The operator moves the lifting/lowering control to the lifting position.The motor starts the pump and the pump draws hydraulic fluid from the tank.

2. The hydraulic fluid flows to the relief valve and through the check valve to the proportional valve (M1) and back to the tank.

3. The proportional valve (M1) is fully open.Then the valve is slightly closed and the pressure increases.This allows stepless control of lifting with loaded forks.

4. The pressurised hydraulic fluid opens the next check valve in M2 and flows to the mast main lift cylinder.

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5.1.3.2. Mast lowering

Figure 5.37. Hydraulic fluid flow during mast lowering

1. The operator moves the lifting/lowering control to the lowering position.The proportional valve (M1) is closed and

M2 is opened.

2. The proportional valve (M1) starts to open slowly.This allows stepless control of lowering.

3. The hydraulic fluid flows through the flow restrictor back to the tank.

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5.1.4. Hydraulic system of trucks with HCU and initial lift (1,200 and 1,600 kg capacity models)

NOTE

Make sure that you have the appropriate maintenance instructions and the schematic diagram for the truck model under maintenance.

Figure 5.38. Hydraulic system, 1,200 and 1,600 kg capacity trucks with HCU and initial lift (TH72 0105)

Figure 5.39. Hydraulic fluid tank with a strainer and filling cap

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