1.38 HYDRAULICS Accumulator (45) The nitrogen charged accumulators (1) provide hydraulic pressure for operation of spools when engine is switched off. The accumulators are attached to brackets, located adjacent to the main hydraulic control valve (25). Specifications Pre-charge pressure 7 bar (100 psi) Oil capacity 0.75 litre Tap (46) 1 Accumulators The tap valve (3) (46) is located on the rear service plate (1) and connects the return line from the autohitch manifold (2) to the hydraulic tank. When operated, the tap valve (3) allows return oil from the autohitch manifold(2) to flow to the hydraulic tank.
The return line downstream from the tap valve (3) connects to the return line from the trailer brake valve (4). The tap valve (3) is used to convert the dual acting service for the autohitch to single acting service for trailer tipping. Trailer brake valve (47) The trailer brake valve, if fitted, is located on the rear service plate and is connected to the inlet section (36) of the main hydraulic control valve (25), the hydraulic tank (1) and the trailer coupling (48). When a trailer brake is connected to the trailer brake coupling and the brakes are applied, the porting of the valve applies proportional pressure to the trailer brake.
When the brakes are released, the valve diverts the hydraulic oil to the hydraulic tank (1). 1 Service plate 3 Tap valve (46) 2 Manifold 4 Trailer valve The valve is pilot operated by a signal taken from the operation of the service brakes. Key to Trailer Brake Valve 1 Outlet to Trailer Brake Coupling (48) 2 Inlet from Tap (46) 3 Pressure supply (B2) Trailer brake coupling (48) The trailer brake coupling (1) is a self-sealing, quick release coupling, located on the rear service plate (2). The coupling is used to connect a trailer braking system to the trailer brake valve (47), if fitted. Key to Trailer Brake Coupling 1 Trailer brake coupling 2 Rear service plate