Product Descreiption
1. Product Parameters
- Part Number: 3943445
- Application: Cummins 6L Series (ISLe, QSL9) diesel engines
- Type: Engine Valve Rocker Arm (intake / exhaust, depends on engine configuration)
- Material: Forged steel / high-strength alloy steel (heat-treated)
- Surface Hardness: HRC 58–62 (typical for wear resistance)
- Bore Diameter (Shaft Hole): ~22 mm (standard for 6L rocker shaft)
- Overall Length: ~135–140 mm
- Mounting Holes: 1 main shaft bore + 1 pushrod seat + 1 valve stem contact pad
- Lubrication: Oil passage for forced lubrication
- OEM Fitment: Direct replacement for original equipment
2. Installation Location
- Mounted On: Cylinder Head of the Cummins 6L engine
- Assembly: Installed on the rocker arm shaft (rocker shaft) in the rocker arm assembly
- Position: Located between the pushrod / tappet (below) and the engine valve stem (above)
- Arrangement: One rocker arm per intake / exhaust valve (total 12 rockers for 6-cylinder 6L engine)
- Access: Under the valve cover / rocker cover on top of the engine
3. Function
- Actuation: Transfers motion from the camshaft → pushrod → rocker arm to open / close intake and exhaust valves
- Lever Action: Acts as a lever to amplify cam lift and convert vertical pushrod motion into downward valve-opening motion
- Valve Control: Precisely controls valve timing, lift, and duration for air intake and exhaust cycles
- Wear Resistance: Hardened contact surfaces to withstand repeated impact with valve stems and pushrods
- Lubrication: Oil passage ensures lubrication to reduce friction and wear at pivot and contact points
