FAW J6P Cylinder Head Cover: Deconstructing 5 Critical Parts for a Leak-Proof Valvetrain

Welcome to this definitive technical analysis of the FAW J6P Cylinder Head Cover (Main Assy P/N 1003031A600-000Z). This is the primary “service door” for the engine on the FAW Jiefang CA3250P66K2L1T1E 6×4 dump truck.

This component is often mistaken for a simple “lid,” but it is a complex, engineered “Logic Assembly” that is critical to engine health.

Its primary logic is twofold: it provides the final “Sealing Logic” for the entire engine, keeping high-pressure oil in and all contaminants out. Secondly, it is the core of the engine’s “Oil Control Logic,” housing the baffle system that manages crankcase vapors. This FAW J6P Cylinder Head Cover is essential for a clean, leak-free, and efficient engine.

The “Sealing & NVH Logic” of the FAW J6P Cylinder Head Cover is its most obvious function. It is the final “roof” over the valvetrain. A failure of its ‘Seal ring’ (gasket) is the most common source of engine oil leaks, which can damage belts and alternators below. Its “NVH Logic” (Noise, Vibration, Harshness) is also critical. The cover is often made from a composite material or stamped steel with damping properties, designed specifically to absorb and muffle the high-frequency “clatter” of the valvetrain, reducing operator fatigue in the cab.

This expert guide is an essential resource for fleet technicians, engine specialists, and parts managers. We will deconstruct the entire 5-component-type group. We will analyze the “Main Cover & NVH” logic (the cover itself), the critical “Oil Baffle & PCV” logic (the internal ‘baffle plate’), and the “Sealing & Fastener” logic that ensures a perfect, long-lasting, vibration-proof seal for the FAW J6P Cylinder Head Cover.

Core 1: The “Sealing & NVH” Logic (Component 1A)

This component is the primary structural part of the assembly, the main cover itself.

1. Component: ‘Cylinder head cover’ (1003031A600-000Z)
This is the main body of the FAW J6P Cylinder Head Cover. Its “logic” is to be a lightweight, yet perfectly rigid and flat “roof.” It is typically made from either a high-temperature composite plastic or a stamped steel alloy. The “structural logic” of this design is to provide a perfectly flat and stable sealing surface that will not warp under the engine’s intense heat cycles. Warping is the primary enemy of a good seal, so the cover is often designed with reinforcing ribs.

Its second “logic” is “NVH Control” (Noise, Vibration, Harshness). A simple metal plate would act like a drum, amplifying the “clatter” of the valvetrain (rocker arms and injectors). This FAW J6P Cylinder Head Cover is engineered to dampen those specific frequencies, often by using a composite “sandwich” material or by being “isolated” from the head by rubber-grommeted bolts. This is a key “comfort logic” component, reducing the noise that reaches the operator in the cab and improving driver focus. It also serves as the main barrier protecting the valvetrain from external contaminants.

Core 2: The “Oil Control & PCV” Logic (Component 1B)

This is arguably the most complex and critical “logic” in the entire FAW J6P Cylinder Head Cover assembly. It is not just a splash guard.

1. Component: ‘Oil baffle assy’ (1003035-600-000Z)
This component, the ‘Oil baffle assy’, is the heart of the engine’s “Positive Crankcase Ventilation” (PCV) system. Here is the “PCV Logic”: All engines have “blow-by,” which is combustion gas that escapes past the piston rings into the crankcase. This gas must be vented, but it is mixed with a heavy “mist” of hot oil. The “logic” of this baffle is to be a “maze.”

The blow-by gas, on its way to the PCV valve (which is usually on the cover), is forced to travel through this baffle. The gas itself can make the sharp turns, but the heavier liquid oil droplets cannot. They have too much inertia. They “impact” on the walls of the baffle, “coalesce” (form into larger drops), and then drip back down onto the valvetrain for lubrication. The now “clean” gas (mostly vapor) exits the PCV valve and is fed back into the engine’s intake to be burned. This “Baffle Logic” is what makes the FAW J6P Cylinder Head Cover an active emissions-control and efficiency device.

If this baffle fails or becomes clogged, the “logic” breaks. Liquid oil will be sucked into the engine’s intake, leading to blue smoke, high oil consumption, and rapid carbon buildup on the intake valves and turbocharger. Therefore, this ‘baffle’ is a critical component of the FAW J6P Cylinder Head Cover.

Core 3: The “Sealing & Fastener” Logic (All Others)

This group contains the components that physically seal the FAW J6P Cylinder Head Cover and provide service access.

1. Component: ‘Seal ring’ (1003036-29D)
This is the main perimeter gasket. Its “logic” is “controlled compression.” It is not a flat paper gasket but an engineered “elastomer” (high-temperature, oil-resistant rubber) seal. It is designed to sit in a groove in the FAW J6P Cylinder Head Cover or the head itself. When the bolts are tightened, the gasket compresses to fill the groove perfectly, creating a 360-degree, durable, oil-tight seal that can flex and move with the engine’s vibrations.

2. Component: ‘Cover’ (1003037-29D)
This is the “Service Access Logic,” commonly known as the oil filler cap. Its “logic” is to provide a reliable, tool-free access point for adding engine oil. It must provide a perfect seal to prevent oil splash and crankcase vapor leaks, which it does via its own integrated O-ring or gasket. It is a critical part of the FAW J6P Cylinder Head Cover‘s user interface.

3. Component: ‘Hexagon flange bolt’ (Q1840510)
This is the “Clamping Force Logic.” The list calls for 12 of these bolts. The “flange logic” is critical: the flange is a built-in washer. This distributes the clamping load from the bolt head over a wider area of the composite or stamped-steel cover, preventing it from cracking. These bolts are often designed with “shoulders” (a specific unthreaded section) that act as a “stop.” This “stop logic” prevents over-tightening, which would crush and destroy the ‘Seal ring’ (Comp 2). The “torque logic” is also vital; these 12 bolts must be tightened in a specific sequence (e.g., center-out) to ensure the FAW J6P Cylinder Head Cover gasket seats evenly.

FAW J6P Cylinder Head Cover Parts List & Specifications

The following table provides the complete, detailed breakdown of all 5 component types identified in this FAW J6P Cylinder Head Cover group for the FAW Jiefang CA3250P66K2L1T1E 6×4 dump truck.

Core Specifications

The specifications for the FAW J6P Cylinder Head Cover are defined by its function as the primary sealing and ventilation component for the valvetrain.