ENGINE G 0311487 - Caterpillar

Illustration 1 g00770722
Carry-Check and Quick-Drop Valve
(1) Vent line to the main control valve for the quick drop
(2) Vent line to the main control valve from the carry-check valve
(3) Oil line from main control valve
(4) Oil line to the main control valve
(5) Oil line to the rod end of the cylinder
Illustration 2 g00770805
(6) Vent to the main control valve for the quick drop
(7) Vent to the main control valve for the carry-check valve
(8) Passage to the main control valve
(9) Passage to the head end of the cylinder
(10) Quick-drop valve
(11) Check valve
(12) Passage to the main control valve
(13) Passage to the rod end of the cylinder
(14) Carry-check valve When the bowl valve stem is in the QUICK-DROP position, passage (6) and passage (7) are open to the tank. Pump oil from the main control valve flows through passage (8), check valve (11) and opening (9) to the head end of the cylinder. Oil from the rod end of the cylinder flows through passage (13) and opens check valve (14). Rod end oil opens quick-drop valve (10). Rod end oil then combines with pump oil in passage (9). The oil flows through opening (9) to the head end of the bowl cylinder. With both the oil and the force of gravity on the scraper, the bowl moves down at a fast rate of speed.When the bowl valve stem is in the LOWER position, passage (6) is closed and quick-drop valve (10) cannot be opened. Oil from the rod end of the cylinder must flow through passage (12) to the implement control valve and into the tank.When the bowl control valve stem is in the HOLD position, both passage (6) and passage (7) are closed. The weight of the scraper cannot pull the rod out of the cylinder because the rod end oil cannot open carry-check valve (14). When the bowl control valve stem is in the RAISE position, oil flows into passage (12) and into the rod end of the cylinder. The oil from the head end of the bowl cylinder opens check valve (11). The oil then flows through passage (9) into passage (8), through the main control valve, and into the tank.