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- Wanda Plaza, Jinan, Shandong, China
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Reliable oil circulation for heavy-duty engines – The OEM W8604040400007 Circular Arc Gear Oil Pump is engineered to deliver consistent oil flow and pressure, ensuring proper lubrication of critical engine and transmission components. Designed for extreme operating conditions, this pump reduces wear and extends component life. For guaranteed compatibility and performance, always choose genuine Sinotruk Homan parts. The circular arc gear profile provides smooth, low-pulsation flow with high volumetric efficiency, making it ideal for construction trucks, mining equipment, and heavy-duty commercial vehicles.
The W8604040400007 circular arc gear oil pump uses a unique tooth profile that reduces fluid shear and turbulence, resulting in higher overall efficiency compared to standard spur gear pumps. The pump delivers a steady flow with minimal pressure ripple, ensuring that bearings and moving parts receive constant lubrication. Its compact design and robust construction make it suitable for engine oil, transmission fluid, and hydraulic oil applications in heavy trucks and off‑highway equipment.
Optimized tooth geometry reduces noise and vibration. The W8604040400007 operates quietly even at high rotational speeds, improving driver comfort and pump longevity.
Housing made of high-strength cast iron, gears from case‑hardened alloy steel. The pump withstands continuous operation at up to 25 bar and temperatures from -30°C to +130°C.
Achieves >90% efficiency across a wide speed range (800‑4000 rpm). Suitable for continuous duty in demanding environments.
| OEM Number | W8604040400007 |
| Product Name | Circular Arc Gear Oil Pump |
| Brand | SINOTRUK Homan |
| Pump Type | External circular arc gear |
| Displacement | 12 cc/rev (standard) |
| Max Flow Rate | 48 L/min @ 4000 rpm |
| Max Continuous Pressure | 25 bar (360 psi) |
| Max Peak Pressure | 30 bar (435 psi) |
| Speed Range | 800 – 4000 rpm |
| Temperature Range | -30°C to +130°C |
| Viscosity Range | 10 – 1000 cSt |
| Inlet/Outlet Ports | G3/4″ BSP (inlet), G1/2″ BSP (outlet) |
| Mounting Flange | SAE A 2‑bolt (82.5 mm pilot) |
| Weight | 4.5 kg |
| Seals | FKM (high temperature, fuel resistant) |
The W8604040400007 circular arc gear pump uses a pair of specially designed gears with involute-circular tooth profiles. This geometry ensures a larger contact ratio, reducing pressure ripple and noise compared to standard involute gears. The housing is precision machined to maintain tight clearances between the gear tips and the bore, minimizing internal leakage and increasing volumetric efficiency. Each pump is dynamically balanced and tested for consistent flow output across the entire speed range. SINOTRUK Homan uses only premium bearing materials and heat‑treated shafts to guarantee long service life.
The W8604040400007 is compatible with engine oils (SAE 10W‑40 to 20W‑50), transmission fluids, hydraulic oils (ISO VG 32‑68), and even some synthetic lubricants. FKM seals provide excellent resistance to high temperatures and chemical additives. The pump can handle small amounts of particulate contamination (up to 50μm) without immediate damage, although a suction strainer is recommended for optimal lifespan.
The W8604040400007 features a standard SAE A 2‑bolt mounting flange and a 14‑tooth splined input shaft, making it a direct replacement for many OEM pumps. It can be driven directly from the engine gear train or via a PTO. The pump is bi‑rotational (clockwise or counter‑clockwise), providing flexibility for different vehicle layouts. For remote mounting, optional adapter plates and flexible coupling kits are available. Installation is straightforward and requires no special tooling.
For correct installation of the W8604040400007, follow these steps: 1) Ensure the pump mounting surface is clean and flat. 2) Lubricate the O‑ring or gasket before assembly. 3) Torque mounting bolts to 45 Nm in a cross pattern. 4) Connect inlet and outlet hoses, ensuring no sharp bends. 5) Prime the pump by filling the inlet port with clean oil before first start. 6) Run the engine at idle and check for leaks and proper pressure. 7) After first 50 hours of operation, re‑torque the mounting bolts.
The W8604040400007 requires minimal routine service. Change the inlet strainer every 1000 operating hours or per vehicle maintenance schedule. If flow or pressure drops, first check for clogged inlet screen, low oil level, or excessive oil viscosity in cold weather. The pump gears are designed to tolerate minor debris, but severe contamination may require professional overhaul. Always use genuine SINOTRUK Homan seal kits for repairs.
The W8604040400007 circular arc gear oil pump is manufactured under IATF 16949 and ISO 9001:2015 certified processes. Each pump undergoes 100% testing: pressure‑flow characterization, volumetric efficiency measurement, and leak test at 1.5× maximum working pressure. The gears are 100% inspected for tooth profile and surface hardness (58‑62 HRC). The pump also meets SAE J1176 fire‑resistant fluid compatibility standards and has CE mark for European markets.
Field tests on 200 SINOTRUK Homan heavy trucks equipped with the W8604040400007 oil pump showed a 15% improvement in oil pressure stability at idle compared to previous designs. After 500,000 km, the average volumetric efficiency remained above 88%. A mining fleet using these pumps in excavators reported zero pump failures over a 3‑year period, despite extreme dust and heat. These results confirm the exceptional durability and reliability of the W8604040400007.
Each W8604040400007 circular arc gear oil pump is supplied in a heavy-duty carton with foam inserts, including the pump, mounting gasket, and installation sheet. A laser-etched serial number and QR code are applied to the housing. Scanning the QR code redirects to the SINOTRUK Homan verification portal, confirming authenticity. Always purchase from authorized distributors to avoid counterfeit pumps with inferior materials and no traceability.
Summary: The SINOTRUK Homan Circular Arc Gear Oil Pump (OEM W8604040400007) delivers reliable lubrication, high efficiency, and long service life. Upgrade your heavy vehicle’s oil system with this genuine OEM component, trusted by fleets worldwide.
If you have any questions about our products, services, or anything related to what we offer, please don’t hesitate to leave us a message—our dedicated team is always ready to provide prompt and helpful responses to address your concerns. What’s more, when you become our valued customer, we’re delighted to offer you complimentary catalog services, giving you access to detailed, up-to-date information on our full range of products, specifications, and offerings to help you make informed decisions.