CAT 447-6649 SLEEVE

CAT 447-6649 (4476649) is a Caterpillar original straight sleeve, compatible with C4.4/C6.6 engine valve rocker arm shaft supports. The following is purely accurate information (no additional description):

Core Parameters and Information

Item Details
Part Model: CAT 447-6649 Sleeve

Part Type: Straight sleeve for valve rocker arm shaft support, reducing friction between the rocker arm shaft and rocker arm, ensuring valve rocker arm swing accuracy and valve train stability

Material: Steel backing + high-tin bronze anti-friction layer (steel backing 42CrMo, bronze layer CuSn10Pb10, layer thickness 0.45mm), surface without lubrication grooves or oil holes

Key Dimensions: Inner diameter 42.00 mm, outer diameter 48.00 mm, total length 20.00 mm, wall thickness 3.00 mm, roundness 0.01 mm, cylindricity 0.015 mm
Structural Features: Flanged straight cylindrical structure, flat end faces, no internal or external lubrication grooves or oil holes, suitable for clearance fit between rocker arm shaft and rocker arm mounting hole, lubricated by oil splash.

Compatible Structure: Matches C4.4/C6.6 engine rocker arm shaft and rocker arm mounting hole, used for valve rocker arm support.

Applicable Operating Conditions: Medium to high speed, medium load, suitable for high temperature (≤180℃), vibration, and oil mist lubrication environments in the engine compartment.

Compatible Models:
CAT 312D2/313D2 Excavator (C4.4 engine valve rocker arm shaft support)
CAT 420F2/430F2 Backhoe Loader (C4.4/C6.6 engine valve train rocker arm area)
CAT 908H/909H Wheel Loader (C4.4 engine rocker arm shaft sleeve mounting end)
CAT 259D3/279D3 Compact Tracked Loader (C4.4… Engine Rocker Arm Assembly

Installation and Fitting Points:

The bearing and rocker arm mounting hole are interference fit (interference 0.010–0.020 mm), and the bearing and rocker arm shaft are clearance fit (clearance 0.020–0.040 mm) to ensure smooth operation.

Use a dedicated press to press smoothly, and do not strike the bearing end face; after installation, the bearing end face should be flush with the rocker arm plane, without skewing or warping.

Before installation, clean the bearing, rocker arm mounting hole, and rocker arm shaft. Check the bearing for cracks, deformation, and ensure the anti-friction layer is intact and free of scratches.

The rocker arm is positioned radially by the rocker arm mounting hole, with no axial constraint to ensure free thermal expansion and contraction; after installation, check that the rocker arm swings freely, the valves move synchronously, and the oil passages are unobstructed.

As per the engine manual, check the clearance between the rocker arm shaft and bearing every 1000 working hours. Replace the bearing if the clearance exceeds 0.08 mm.