CARRIER ASSEM. 5T2619 - Caterpillar

At operating temperature, the hydraulic oil tank is hot and under pressure. Hot oil can cause burns. Remove the breather filter cap only when the engine is stopped and the breather filter cap is cool enough to touch. Slowly loosen the breather filter cap to release any pressure in the hydraulic tank. Be cautious of hot hydraulic oil when any lines are disconnected in the hydraulic system.
1. Disconnect three wire assemblies (3) and wire assembly (4).2. Disconnect five hose assemblies (2).3. Remove three nuts (1) and washers that holds the retarder control valve to the frame of the machine and remove the retarder control valve. For installation of the retarder control-air valve, reverse the removal steps. Refer to the Topic" Lubricant Viscosities and Refill Capacities" in the Operation and Maintenance Manual for the proper filling procedure and the proper levels for the hydraulic system and the cooling system.Disassemble & Assemble Retarder Control Valve
Start By:a. remove retarder control valve 1. Remove nut and washer (1). Remove coil assembly (2) as shown. 2. Remove cartridge assembly (3). 3. Remove backing ring (6). O-ring seal (5), and O-ring seal (4) from cartridge assembly (3). 4. Remove nut and washer (7) and remove coil assembly (8). 5. Remove cartridge assembly (9). 6. Remove backing ring (14), O-ring seal (13), backing ring (12), O-ring seal (11), and O-ring seal (10) from cartridge assembly (9).7. Repeat steps 4, 5 and 6 to remove the remaining coil and cartridge assembly. 8. Remove pressure switch and fitting (15). 9. Remove internal orifice plug (16). Orifice plug (16) is located under pressure switch and fitting (15).10. Remove O-ring seal on orifice plug (16) and pressure switch fitting (15). 11. Repeat step eight for the removal of plug (17), fitting (18), and fitting (19). Each port has an internal orifice plug similar to item (16). Do not intermix the orifice plugs. The orifice plugs must be installed in the port they were removed.12. Remove the remaining plugs and fittings to replace O-ring seals if necessary. The following steps are for the assembly of the retarder control valve. 13. Install orifice plug (16) and pressure switch (15). Photograph shows plug (17), fitting (18) and fitting (19) installed. The orifice plugs must be installed in the port they were removed from. Do not intermix the orifice plugs. 14. Install O-ring seal (10), O-ring seal (11), backing ring (12), O-ring (13), and backing ring (14) on cartridge assembly (9). 15. Lubricate O-ring seals with hydraulic oil and install cartridge assembly (9) in valve body. Tighten cartridge assembly (9) to a torque of 25 5 N m (18 4 lb ft). 16. Install coil assembly (8) as shown. Fasten coil assembly to the cartridge assembly with the nut and washer (7). Tighten nut (7) to a torque of 3.0 0.5 N m (27 4 lb in).17. Repeat steps 3 and 4 for the remaining cartridge and coil. 18. Install O-ring seal (4), O-ring seal (5), and backing ring