Buffer Seal Assembly May Wear and Cause Leaks in the head of the Lift Cylinder on Certain Track-Type Tractors and Wheel Dozers{5102} Caterpillar

Track-Type Tractor:

D10 (S/N: 84W1-UP)

D10N (S/N: 2YD1-UP; 3SK1-UP)

D10R (S/N: 3KR1-UP; AKT1-UP)

D10T (S/N: RJG1-UP)

D11R (S/N: AAF1-UP; 8ZR1-UP; 9TR1-UP; 9XR1-UP; 7PZ1-UP)

D11T (S/N: AMA1-UP; GEB1-UP; TPB1-UP; MDG1-UP; JEL1-UP; JNS1-UP)

Wheel Dozer:

854G (S/N: A4W1-UP)

Introduction

The problem that is identified in the technical information bulletin that follows does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.

Problem

Illustration 1	g03347154

The 167-2216 Buffer Seal As (1) is wearing into 162-7757 Head for the lift cylinder and is causing leaks on D11R and D11T machines. This failure occurs at high hours greater than 5000. This failure mode has also been recognized on the 162-7487 Head for the lift cylinders on the D10N, D10R, and D10T.

Solution

Illustration 2	g03380712

Caterpillar is aware of this problem, and is recommending the following Interim Repair.

Inspect the head for wear in the buffer seal groove. If the worn groove is less than 0.5 mm (0.02 inch) (A), machine the groove out. Refer Illustration 2. A slightly wider groove is acceptable for reuse. If the groove is much wider, replace with the same part.

Continuous Product Improvement (CPI) team is in the process of validating a potential permanent solution for this issue.