ENGINE AR BSC 7C0574 - Caterpillar

Illustration 1 g01263313
Hoist cylinders (1) Rod assembly (2) Cylinder (second stage) (3) Cylinder (first stage)
Illustration 2 g00281531
Cross section of hoist cylinder (1) Rod assembly (2) Cylinder (second stage) (3) Cylinder (first stage) (4) Grooves in the end of the cylinder (second stage) (5) Chamber in the head end of the hoist cylinder (6) Opening to the head end of the hoist cylinder (7) Opening to the rod end of the hoist cylinder (8) Chamber between cylinders (first stage and second stage) (9) Chamber between the rod assembly and cylinder (second stage) (10) Orifices in the rod assembly (11) Head (12) Internal head (13) PistonRaising the Truck Body or the Water Tank
Illustration 3 g00281955
Hoist cylinder (first stage) to extended length (1) Rod assembly (2) Cylinder (second stage) (3) Cylinder (first stage) (4) Grooves in the end of the cylinder (second stage) (5) Chamber in the head end of the hoist cylinder (6) Opening to the head end of the hoist cylinder (7) Opening to the rod end of the hoist cylinder (8) Chamber between cylinders (first stage and second stage) (9) Chamber between the rod assembly and cylinder (second stage) (10) Orifices in the rod assembly (11) Head (12) Internal head (13) Piston (AA) Pump oil (LL) Return oil
Illustration 4 g00281956
Extended hoist cylinder (1) Rod assembly (2) Cylinder (second stage) (3) Cylinder (first stage) (4) Grooves in the end of the cylinder (second stage) (5) Chamber in the head end of the hoist cylinder (6) Opening to the head end of the hoist cylinder (7) Opening to the rod end of the hoist cylinder (8) Chamber between cylinders (first stage and second stage) (9) Chamber between the rod assembly and cylinder (second stage) (10) Orifices in the rod assembly (11) Head (12) Internal head (13) Piston (AA) Pump oil (LL) Return oilTwo hydraulic cylinders are used to move the truck body or the water tank away from the truck. When the hoist control is held in the RAISE position, the pump oil extends the two-stage cylinders and the truck body or the water tank is raised to the dump position.The hoist cylinders raise the truck body or the water tank in two stages. The pump oil flows into opening (6) to the head ends of the hoist cylinders. The oil flows through a tube in rod assembly (1) and into chamber (5) in the head end of cylinder (3). The pressure of the pump oil in chamber (5) moves cylinder (3) .The oil in chamber (8) must now flow through grooves (4) in the end of cylinder (2) and into chamber (5) .When head (11) on the end of cylinder (3) reaches a lip on the end of cylinder (2), the cylinder is also pushed up by the oil in chamber (5). The oil in chamber (9) now flows through orifices (10), through the tube in rod assembly (1), and through opening (7) to the hoist control valve.Cylinder (2) is pushed until internal head (12) on the end of cylinder (2) contacts piston