Undersized Front Track Roller Frame Bearing{4151} Caterpillar

Track-Type Tractor:

D8R Series II (S/N: AKA1-UP; 6YZ1-UP)

D8R (S/N: 9EM1-UP)

D8T (S/N: J8B1-UP)

Introduction

The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.

Problem

The D8R and D8R Series II has experienced failures with the chrome sleeve that is located on the front track roller frame. The chrome sleeve has moved out of location. This is due to an undersized diameter on the frame assembly. This causes the oil to leak between the front track roller frame and the rear track roller frame. This does not allow the seal to press against the platform firmly.

The recoil tube develops oil leaks at the seal between the front track roller frame and the rear track roller frame. Two possible root causes may exist. The weld on the undersized bores can cause the frame to fail.

Solution

If the chrome sleeve has slipped due to an undersized bearing diameter on the front track roller frame, a weld is not permitted. A new front track roller needs to be installed. If a crack is present on the bearing diameter of the front track roller frame, the frame must be replaced. Process controls are in place at the manufacturing facility in order to prevent a undersized bearing diameter on a front track roller frame.

Illustration 1	g01945400
(A) 660 mm (25.98 inch) (B) 321 mm (12.64 inch)

Note: Dimension (B) represents a no weld area.