- Backhoe Loader:
- 420D (S/N: BLN4544-UP; FDP7199-UP)
- 430D (S/N: BNK2502-UP; BML2281-UP)
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| Illustration 1 | g01163596 |
Machines can be equipped with a standard stick on the backhoe and the 201-0664 Control Valve Gp to operate auxiliary work tools. During the operation of other backhoe circuits, movement of the auxiliary work tools have been observed without action by the operator.
During the operation of other backhoe circuits, oil flows into the auxiliary control valve. This oil contacts the 132-5303 Relief Valve (1) which is a makeup and relief valve. Some of the oil flows through the makeup and relief valve which causes the work tools to move. If the 190-3450 Control Valve Gp is installed on the machines, no movement has been observed.
The movement of the auxiliary work tools without action by the operator can be controlled. Remove the 132-5303 Relief Valve (1). Install the 6E-6283 Relief Valve in the control valve group. The 6E-6283 Relief Valve is not a makeup and relief valve.
The replacement of the 201-0664 Control Valve Gp with the former 190-3450 Control Valve Gp is not necessary. The installation of the 6E-6283 Relief Valve should resolve the problem.