The Clutch Three Pilot Pressure Orifice May Become Blocked Within the Clutch Housing of Certain C-Series Articulated Trucks {3030, 3160, 3169} Caterpillar

Articulated Truck

735C (S/N: LFJ1-UP; TFJ1-UP)

740C EJECTOR (S/N: LFN1-UP; TFN1-UP)

745C (S/N: JE81-UP; JE91-UP; LFK1-UP; TFK1-UP)

Introduction

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

Problem

The clutch three pilot pressure orifice may become blocked within the clutch housing of the products listed above. Debris may become trapped within the 0.5 mm (0.02 inch) orifice which provides pilot pressure from clutch three and prevents the auto engagement of clutch six piston. Blocked pilot pressure may cause erratic clutch three and clutch six fills resulting in poor shift quality and reduced friction disc life.

Solution

Illustration 1	g06196978
Orientation view of the clutch housing (A) Clutch Housing

During rework procedures involving clutch housing (A), inspect the pilot pressure orifice with tag wire and a flash light. The orifice can be cleared with a torch tip cleaning tool to remove burrs and tag wire to help clear debris. A flash light can be used to confirm that the orifice is clear. Refer to Illustration 1 for the orifice location with in clutch housing (A).

Note: For additional assembly instructions of the transmission planetary, refer to Disassembly and Assembly, UENR4227, " Transmission Planetary - Assemble".