- ChangChun City, Jilin Province, China
by 
Welcome to this expert technical guide on the FAW Power Steering Pump (Part No. 3407020-93W-C00), the hydraulic heart of the steering system for the FAW Jiefang CA4251P66K24T1A3E5 6×4 diesel semi-trailer tractor. This component is essential for driver control and safety.
The function of the FAW Power Steering Pump is to provide hydraulic assistance, reducing the immense physical effort required to turn the front wheels of a fully-loaded tractor. It does this by generating high-pressure hydraulic fluid (often exceeding 1,500 PSI) that is fed to the steering gear.
This in-depth guide is a critical resource for professional technicians and fleet managers. We will deconstruct the entire FAW Power Steering Pump mounting assembly into its 3 smallest serviceable units: the main pump, its critical mounting gasket, and the high-tensile fasteners that secure it to the engine.
The main component is the ‘Power Steering Pump Assembly’ (3407020-93W-C00). This is the heart of the hydraulic assist system. For a heavy-duty diesel engine, the FAW Power Steering Pump is not a belt-driven accessory as in a passenger car. Instead, it is a robust, gear-driven pump that mounts directly to the engine’s timing gear case. This direct gear-drive is essential for reliability, as it eliminates the risk of a slipping or breaking belt, which would instantly make the truck incredibly difficult to steer.
This FAW Power Steering Pump is a positive-displacement pump, most likely a high-volume **gerotor** or **vane-type** pump. In a vane pump design, a slotted rotor spins inside an eccentric (off-center) housing. Vanes slide in and out of the rotor slots, creating expanding chambers on the inlet side (which draw in low-pressure fluid from the reservoir) and shrinking chambers on the outlet side. This “shrinking” action is what compresses the fluid and generates the high pressure needed for the steering gear.
A critical feature of the FAW Power Steering Pump is its internal **flow control valve**. This valve is essential because a gear-driven pump’s output volume increases with engine RPM. If uncontrolled, the steering would be overly sensitive at high speeds and normal at idle. The flow control valve, which is a spring-loaded spool valve, bleeds off excess fluid at higher RPMs, ensuring that the *volume* of fluid sent to the steering gear is constant. This provides a consistent, predictable steering “feel” whether the truck is idling or at highway speed.
Also housed within the FAW Power Steering Pump assembly is a **pressure relief valve**. This is a safety poppet valve. When the driver turns the steering wheel all the way to a “lock” (e.g., in a parking lot), the steering gear is blocked and can no longer accept fluid. The pressure in the hose would spike almost instantaneously, high enough to rupture the hose or damage the pump. The relief valve senses this pressure spike (e.g., >1500 PSI) and opens, dumping the high-pressure fluid directly back to the inlet side, protecting the entire system. The “whine” you hear when holding the wheel at a full lock is the sound of this valve in operation. A failure of the FAW Power Steering Pump often means one of these internal valves has failed, or the gerotor/vane assembly itself is worn out, causing low pressure and stiff steering.
The ‘Gasket-Power Steering Pump’ (3407024-26D) is the single most critical serviceable part in this assembly. Because the FAW Power Steering Pump is gear-driven, it mounts directly to the engine’s timing gear case with a flange, just like the fuel injection pump or air compressor. This one gasket must seal this complex interface.
This gasket has two primary, high-stakes functions. First, it must seal the “clean” hydraulic steering fluid from the “dirty” engine oil. The main drive gear of the FAW Power Steering Pump is lubricated by the engine’s timing gear case, which is filled with engine oil. The pump’s main shaft must pass through this interface. This gasket (along with a shaft seal) prevents the two fluids from ever mixing. A failure here would contaminate the entire power steering system with abrasive engine oil and soot, destroying the steering gear.
Second, this gasket must also seal the pump’s internal hydraulic passages. The FAW Power Steering Pump‘s flange has a low-pressure “inlet” port (drawing fluid from the reservoir) and a high-pressure “outlet” port (feeding the steering gear). This gasket creates a high-pressure seal for the outlet port, preventing 1,500+ PSI hydraulic fluid from leaking externally.
A failure of this gasket on the inlet side would cause the FAW Power Steering Pump to suck in air, leading to cavitation (a loud whining or grinding noise) and foamy, unresponsive steering. A failure on the outlet side would result in a massive, high-pressure hydraulic fluid leak. This gasket is a non-reusable, “replace-on-sight” component.
The final components listed are the two ‘Hex flange bolt, coarse rod (Standard Type)’ (Q1841030) fasteners. These are the two high-tensile bolts that secure the entire FAW Power Steering Pump assembly to the engine’s gear case.
These bolts must perform a critical task: they must provide the precise and even clamping force required to compress the ‘Gasket-Power Steering Pump’ (3407024-26D) and create a perfect seal. Furthermore, they must resist the immense rotational “shearing” force that the drive gear exerts on the FAW Power Steering Pump.
The “flange” head design is a deliberate engineering choice. The integrated washer head distributes the clamping load over a wider surface area of the pump’s mounting flange. This is critical to prevent the hard steel bolt from cracking the (likely) aluminum pump housing, and it also resists loosening from the constant vibration of the diesel engine. The integrity of the FAW Power Steering Pump‘s mount is entirely dependent on these two high-strength bolts.
The following table provides the complete, detailed breakdown of all 3 components identified in the ‘Power Steering Pump’ diagram for the FAW CA4251P66K24T1A3E5 tractor. A professional service of the FAW Power Steering Pump requires replacing the gasket.
| Mark | Part No. | Part Name | Quantity |
|---|---|---|---|
| 1 | Q1841030 | Hex flange bolt, coarse rod (Standard Type) | 2 |
| 2 | 3407020-93W-C00 | Power Steering Pump Assembly (as-per-sample) | 1 |
| 3 | 3407024-26D | Gasket-Power Steering Pump | 1 |
The specifications for the FAW Power Steering Pump are defined by its function as a high-pressure, gear-driven hydraulic pump. The reliability of the FAW Power Steering Pump is critical for vehicle control.
| Vehicle Application | FAW Jiefang CA4251P66K24T1A3E5 6×4 Tractor |
| Component Group | FAW Power Steering Pump |
| Main Pump Assembly P/N | 3407020-93W-C00 |
| Pump Type | Positive Displacement (Vane or Gerotor Type) |
| Drive System | Direct-driven (from Engine Timing Gear) |
| Internal Regulation | Internal Flow Control Valve & Pressure Relief Valve |
| Main Gasket P/N | 3407024-26D (Mounting Flange Gasket) |
| Mounting Fasteners | 2x Hex Flange Bolts (Q1841030) |
| Associated Fluid | Power Steering Hydraulic Fluid |
| Primary Function | Generates high-pressure hydraulic fluid to provide steering assist, reducing driver effort. |
FAW parts, including the Cylinder Block Assembly, are packaged with care to ensure safe delivery. Each component is secured in protective materials to prevent damage during transit. The logistics network guarantees timely shipments worldwide, supporting efficient maintenance operations. Below is an image illustrating the standard packaging for FAW truck parts, showcasing the attention to detail in handling and storage.
This packaging approach minimizes the risk of corrosion or impact damage, ensuring that parts like the FAW Cylinder Block Assembly arrive in perfect condition. Customers can rely on FAW’s logistics for consistent quality and reliability.
FAW is one of China’s oldest and largest automotive manufacturers, with registered capital of RMB 35.4 billion yuan and total assets of RMB 457.83 billion yuan.
CHINA FAW GROUP CO., LTD. (short for FAW), formerly China First Automobile Works, can trace its roots back to Jul 15, 1953, when its first assembly plant started to be constructed. FAW is one of China’s oldest and largest automotive manufacturers, with registered capital of RMB 35.4 billion yuan and total assets of RMB 457.83 billion yuan.
China heavy truck sales global “five in a row”, heavy truck sales global “six in a row”, tractor sales for 16 consecutive years absolute leading industry.
