GUARD 6Y5024 - Caterpillar

Illustration 1 g00318128
Installed Compression Brake (1) Rear housing. (2) Front housing. (3) Stud. (4) Support bracket. The compression brake consists of two different housings. Both brake housings are installed in the compartment for the valve mechanism above the rocker arms and the rocker arm shaft. Each brake housing is positioned over three cylinders. Each brake housing is mounted on a support bracket (4) at the end of the rocker shaft brackets. Special adjustment screws for the exhaust rocker arm and exhaust valve bridges are necessary. Note: The operation of the compression brakes only uses the exhaust side of the engine valve mechanism.A spacer is used between the cylinder head and the valve cover for the installation of the valve cover. With an installed compression brake, this increase in height is 90 mm (3.5 inch). The front compression brake housing and the rear compression brake housing consist of the following parts:
Three master pistons
Three slave pistons
Three control valves
One solenoid valveEngine Compression Brake's Operation
Illustration 2 g00322183
Master-Slave Circuit Schematic (1) Solenoid valve (2) Spring (3) Control valve (4) High pressure oil passage (5) Slave piston adjustment screw (6) Master piston (7) Spring (8) Rocker arm adjustment screw (9) Rocker arm (10) Slave piston (11) Exhaust pushrod (12) Exhaust valves (13) Ball check valve (14) Oil passage from manually operated control switch (15) Low pressure oil passageThe compression brake operates with engine oil. The engine oil is supplied from the rocker arm shafts. Solenoid valve (1) controls the oil flow in the brake housing. When the solenoid is activated, solenoid valve (1) moves down. The downward movement of the solenoid valve closes the oil drain passage to the oil pan. At the same time, solenoid valve (1) opens low pressure oil passage (15) to three control valves (3). As low pressure passage (15) is filled with engine oil, control valves (3) are pushed up in the chamber against the force of spring (2). At this position, a groove in control valve (3) should align with high pressure oil passage (4). This oil passage supplies high pressure oil to slave piston (10) and master piston (6). The engine oil pressure will now lift ball check valve (13). The engine oil pressure also fills high pressure oil passage (4) and the chambers behind the pistons (master-slave circuit). This pressure moves the pistons downward. Then, the pistons can contact the engine valve mechanism. When the oil pressure is the same pressure through all the oil passages, the small spring will force ball check valve (13) against the seat of the ball check valve. The system is completely pressurized, and the system is ready for operation with the engine valve mechanism. When the solenoid is activated, the compression brake is ready to operate in approximately 1/5 of a second.
Illustration 3 g00318164
Oil Passage Schematic (Front Housing) (1) Solenoid valve. (3) Control valves. (4) High pressure oil passage. (6) Master pistons. (10) Slave pistons. (15) Low pressure oil passage.When engine pushrod (11) for the exhaust valve begins to move up