Duramax LLY – TORSIONAL DAMPER AND CRANKSHAFT PULLEY INSTALLATION

1. Install damper key in crankshaft (Figure 2-186).

2. Lubricate crankshaft hub, damper seal contact surface, and damper hub bore with engine oil or chassis grease.

3. Align and install damper on crankshaft.

4. Install washer and damper bolt. Tighten bolt 200 lb-ft (270 Nโ€ขm) torque. Have helper prevent crankshaft from turning with holding tool installed on flywheel.

Fan and Pulley Installation

1. Install crankshaft pulley and bolts (Figure 2-187).

2. Slide fan onto clutch and install bolts finger tight.

3. Install fan and clutch assembly on water pump shaft.

4. Hold water pump shaft with spanner Jโ€“41240-1 and tighten clutch nut to 80-100 lb-ft (108-135 Nโ€ขm) with wrench Jโ€“41240-5A.

5. Torque fan bolts to 15-20 lb-ft (20-27 Nโ€ขm).