FAW J6P Pulley: Deconstructing the 4-Part Logic for a Flawless Accessory Drive

Welcome to this expert analysis of the FAW J6P Pulley (P/N 1005046-36D), the core of the Front-End Accessory Drive (FEAD) system for the FAW Jiefang CA3250P66K2L1T1E 6×4 dump truck.

This component is not a standalone part; it is a critical piece of the “Crankshaft Logic Assembly,” which also includes the ‘Silicone oil damper’ (1005190-36D).

The “logic” of the FAW J6P Pulley is twofold: it must transfer rotational power from the crankshaft to all engine accessories (like the alternator and water pump), and it must survive the engine’s most destructive force—torsional vibration.

The “Torsional Logic” is the key to this entire assembly. A heavy-duty diesel engine does not spin smoothly; it fires in six violent “punches” per cycle. This creates a destructive twisting and untwisting force on the crankshaft. This vibration, if unmanaged, will shred the serpentine belt and destroy the bearings in the alternator and water pump. This is why the FAW J6P Pulley (Comp 2) is not bolted directly to the crank; it is bolted *to* the ‘Silicone oil damper’ (Comp 3). The damper and pulley work as a single, tuned unit. The FAW J6P Pulley is the “interface” for the belt, and the damper is the “absorber” for the vibration.

This technical guide is an essential resource for chassis technicians, engine specialists, and parts managers seeking to understand the complete front-end drive system. Although the master parts list (9) includes the entire crankshaft, we will deconstruct the four *primary* components of the “Front-End Logic” relevant to the FAW J6P Pulley: the “Accessory Drive Logic” (the pulley itself), the “NVH Damping Logic” (the silicone oil damper), the critical “Sealing Logic” (the front oil seal), and the “Fastener Logic” (the specialized damper bolts).

Core 1: The “Accessory Drive” Logic (Component 2)

This is the primary component of the FAW J6P Pulley system, the part that makes physical contact with the serpentine belt.

1. Component: ‘Multi-groove belt pulley – crankshaft’ (1005046-36D)
This component (Comp 2) is the “Power Take-Off Logic.” Its sole function is to transfer the rotational energy of the crankshaft to the engine’s “accessories”—the water pump (for cooling), the alternator (for electricity), the A/C compressor, and the power steering pump. The “multi-groove” (or “serpentine”) design is a modern, high-efficiency logic. It uses a single, wide, flat belt with multiple “V” grooves, which provides a much larger contact patch for grip, reduces slippage, and lasts significantly longer than older, multiple V-belt systems.

The “Material & Balance Logic” of this FAW J6P Pulley is also critical. It is made from heavy-duty, nodular cast iron and is “dynamically balanced” at the factory. This means it is weighted to spin perfectly true, with zero “wobble” (runout). An unbalanced FAW J6P Pulley would cause intense vibration, which would quickly destroy the serpentine belt and, more importantly, the internal bearings of the accessories it drives, leading to premature water pump or alternator failure.

Core 2: The “NVH Damping” Logic (Components 1, 3)

This group is the essential partner to the FAW J6P Pulley. Its “logic” is to absorb the destructive torsional vibrations from the crankshaft.

1. Component: ‘Silicone oil damper’ (1005190-36D)
This (Comp 3) is the “Harmonic Damper” or “Harmonic Balancer.” It is the most critical “NVH Logic” component on the entire engine. Its “logic” is to be a tuned “shock absorber” for the crankshaft. It consists of a heavy, outer “inertia ring” that is separated from the inner “hub” by a layer of thick, viscous silicone fluid. As the crankshaft violently twists and untwists (torsional vibration), the inner hub moves with it. The heavy outer ring resists this change in speed, and the “shearing” of the silicone fluid between them absorbs this violent energy, converting it into harmless heat.

The FAW J6P Pulley (Comp 2) bolts directly *to* this damper, not the crank. This “Isolation Logic” is what saves the pulley and the belt from being destroyed by these vibrations. A failed damper (e.g., if the fluid leaks out) will cause a severe, low-RPM vibration and will quickly lead to the failure of the FAW J6P Pulley or even a snapped crankshaft.

2. Component: ‘Damper bolt’ (1005048K29D)
These six (6) bolts (Comp 1) are the “Fastener Logic” for the damper. They are high-tensile, load-critical fasteners that hold the entire damper and FAW J6P Pulley assembly onto the nose of the crankshaft. These bolts are often “Torque-to-Yield” (TTY) and single-use.

Core 3: The “Sealing & Internal Drive” Logic (Components 4, 7, 8)

This group manages the “interface” between the spinning FAW J6P Pulley assembly and the stationary engine block, as well as driving internal components.

1. Component: ‘Front oil seal’ (1005050-29D)
This (Comp 4) is the “Dynamic Sealing Logic.” It is a high-temperature, oil-resistant rubber lip seal. Its “logic” is to be pressed into the engine’s stationary “front cover” while its inner lip rides on a smooth, polished “sleeve” on the back of the damper hub. This creates a perfect seal, preventing oil from leaking out of the “front main” of the crankcase. A failure here is a common problem that will sling engine oil all over the FAW J6P Pulley and the serpentine belt, causing the belt to slip, squeal, and fail prematurely.

2. Components: ‘Crankshaft timing gear’ (1005037-29D) & ‘Oil pump drive gear’ (1005039-36D)
These gears (Comp 7 & 8) are located *behind* the damper, on the same crankshaft. Their “logic” is to drive the engine’s “internals.” The ‘Timing gear’ drives the camshaft (for the valves) and/or the injection pump. The ‘Oil pump drive gear’ drives the engine’s oil pump. They are part of the master “crankshaft” assembly list that the FAW J6P Pulley belongs to.

Core 4: The “Master Assembly” Context (Components 6, 12, 13)

To fully understand the FAW J6P Pulley‘s role, it is essential to see its place in the “master” assembly. The parts list provided is for the entire crankshaft group, from front to back.

1. Component: ‘Crankshaft’ (1005014-36D)
This (Comp 6) is the “Spine Logic.” The FAW J6P Pulley and damper bolt to the “front nose” of this forged steel shaft. The ‘Crankshaft’ is the central component that carries power from all six pistons.

2. Component: ‘Flywheel’ (1005121-630-0000)
This (Comp 12) is the “Inertia Logic,” located at the *opposite* end of the crankshaft from the FAW J6P Pulley. Its massive weight stores rotational energy to smooth out the engine’s pulses and provides the friction surface for the clutch.

3. Component: ‘Flywheel bolt’ (1005071K29D)
These ten (10) bolts (Comp 13) are the “Rear Fastener Logic.” They secure the flywheel to the rear flange of the crankshaft. Like the damper bolts, these are single-use TTY bolts. Understanding this full assembly—from the FAW J6P Pulley at the front to the flywheel at the back—is key to proper engine service.

FAW J6P Pulley & Crankshaft Assembly Parts List

The following table provides the complete, detailed breakdown of all 14 component types in the master crankshaft assembly, which includes the FAW J6P Pulley, for the FAW Jiefang CA3250P66K2L1T1E 6×4 dump truck.

Core Specifications

The specifications for the FAW J6P Pulley are defined by its function as the power take-off for the engine’s front-end accessory drive.