349E Excavator Hydraulic System Travel Motor Caterpillar


Travel Motor
`



Illustration 1g02174016

Travel motor

(1) Shaft

(2) Piston

(3) Spring

(4) Housing

(5) Valve plate

(6) Head

(7) Passage

(8) Passage

(9) Passage

(10) Swashplate

(11) Guide

(12) Retainer

(13) Shoe

(14) Piston

(15) Barrel

(16) Separator plate

(17) Friction plate

(18) Piston

(19) Passage

(20) Passage

(21) Spring

(22) Port

(23) Port

(24) Displacement change valve

(25) Port

(26) Body

(27) Spring

(28) Spool




Illustration 2g02175200

Travel motor (partial schematic)

(2) Piston

(8) Passage

(9) Passage

(10) Swashplate

(22) Port

(23) Port

(24) Displacement change valve

(29) Drain port

The travel motor can be divided into the following three groups:

  • The rotary group consists of the following components: drive shaft (1), ball guide (11), shoes (13), retainer (12), piston (14), barrel (15) and spring set (3) .

  • The parking brake group consists of the following components: separator plate (16), friction plates (17), brake piston (18) and springs (21) .

  • The displacement change valve consists of the following components: piston (2) and displacement change valve (24) .

The flow of the pump oil depends on the direction of travel. Pump oil flows into the travel motor through port (22) or port (23). Pump oil is forced out of the travel motor through port (22) or (23). The case drain oil that has leaked returns to the tank through drain port (29) of head (6) .

Supply oil from the idler pump flows into the left travel motor through port (23) during forward travel. The oil from port (23) flows through passage (9) in head (6). The oil then flows through passage (20) of valve plate (5). The oil then flows through passage (19) of barrel (15). The oil forces piston (14) to move to the left.




Illustration 3g02175460

Motor passage (side view from head)

(A) Top center

(B) Outlet side (low pressure)

(C) Bottom center

(D) Inlet side (high pressure)

(30) Passage (barrel)

(31) Passage (valve plate)

(32) Passage (valve plate)

Shoe (13) is coupled to the piston. Shoe (13) and the piston slide on the surface of swashplate (10) from the top center to the bottom center. Shoe (13) and the piston rotate with barrel (15). The pistons force oil out of the outlet side of the motor passage. The oil flows through passage (30) and passage (32) of valve plate (5). The oil then flows through port (22). The barrel turns counterclockwise.

Shaft (1) is splined to barrel (15). The shaft and barrel rotate counterclockwise for forward travel.

In reverse travel, port (23) functions as an oil return port. Port (22) functions as a supply port. The left travel motor rotates clockwise.

Pump oil through port (22) turns the right travel motor clockwise for forward travel. Pump oil through port (23) turns the right travel motor counterclockwise for reverse travel.

Information System:

320E and 323E Excavators Cooling System Coolant Sample (Level 1) - Obtain
2010/06/23 Incorrect Use of the Engine Oil Drain Coupling on Some Large Excavators, Off-Highway Trucks/Tractors, Track-Type Tractors, Wheel Dozers, and Wheel Loaders {1306, 1308, 1318}
312D and 313D Excavators Machine System Specifications Blade Cylinder Lines
312D and 313D Excavators Machine System Specifications Blade Cylinder Lines
349E Excavator Hydraulic System Control Valve (Stick Lowering)
Rust on D Series Excavators{0652}
312D and 313D Excavators Machine System Specifications Blade Cylinder Lines
Installation Procedure for Product Link PL522 and PL523 (Cellular) {7606}
374D Excavator Hydraulic System Main Pump (Destroke Pressure) - Test and Adjust
349E Excavator Hydraulic System Stick Drift Reduction Valve
374D Excavator Hydraulic System Travel on Level Ground - Test - Optional Test
374D Excavator Hydraulic System Main Pump (Flow) - Test - Constant Horsepower Flow Control
Procedure to Repair Layered Doors on E Series Excavators{7273}
390D Excavator Hydraulic System Main Hydraulic System
390D Excavator Hydraulic System Pilot Hydraulic System
C4.4 Industrial Engine Connecting Rod
C4.4 Industrial Engine Connecting Rod - Inspect
C4.4 Industrial Engine Finding Top Center Position for No. 1 Piston
C4.4 Industrial Engine Fuel Injection Timing - Check
312D and 313D Excavators Machine System Specifications Stick - 2.50 m (8.202 ft)
349E Excavator Hydraulic System Bucket Hydraulic System
345D MHPU and 349D MHPU Mobile Hydraulic Power Units Joystick Controls Alternate Patterns - If Equipped
2010/06/25 A New Multi Combined Function - Work Tool Valve (MCV) is Now Used on Certain Wheeled Excavators {5064}
320E and 323E Excavators Engine Oil Level - Check