Upright SL-26, Service & Parts Manual

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3. Service and Repair
3-8
3.1 H
YDRAULIC
M
ANIFOLD
Though it is not always necessary to remove the manifold to perform maintenance procedures, a determination
should be made prior to beginning as to whether or not the manifold should be removed before maintenance
procedures begin.
Removal
1. Disconnect the battery ground cable.
2. Tag and disconnect the solenoid valve leads.
3. Tag, disconnect and plug hydraulic hoses.
4. Remove the bolts that hold the manifold to the mounting bracket.
5. Remove manifold block.
Disassembly
Note: Mark all components as they are removed so as not to confuse their location during assembly.
Refer to Valve Block Drawing and Schematic often to aid in disassembly and assembly.
1. Remove coils from solenoid valves.
2. Remove spool valve covers and spool valves.
3. Remove solenoid valves, main relief valve, counterbalance valves and emergency lowering valves.
Remove fittings, plugs, springs, balls and orifices.
Cleaning and Inspection
4. Wash the manifold in cleaning solvent to remove built up contaminants and then blow out all passages with
clean compressed air.
5. Inspect the manifold for cracks, thread damage and scoring where O-rings seal against internal and
external surfaces.
6. Wash and dry each component and check for thread damage, torn or cracked O-rings and proper
operation.
7. Replace parts and O-rings found unserviceable.
Assembly
Note: Lubricate all O-rings before installation to prevent damage to O-rings. Seat all balls in manifold
block by lightly tapping on the ball with a brass drift.
1. Install fittings, plugs, balls and orifices. Use one drop of Locktite #242 on each screw-in orifice.
2. Install emergency lowering valve, counterbalance valves, main relief valve, brake pressure reducing valve,
solenoid valves and spool valves.
3. Install coils on solenoid valves.
Installation
1. Attach manifold assembly to mounting plate with bolts.
2. Connect solenoid leads (as previously tagged).
3. Connect hydraulic hoses. Be certain to tighten hoses to manifold.
4. Operate each hydraulic function and check for proper operation and leaks.
5. Adjust all hydraulic pressures according to instructions.