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The WG9725550198 Pipe Fitting is a 90‑degree elbow designed to connect oil lines with 16 mm outer diameter and 2 mm wall thickness. It is commonly used in SINOTRUK Sitrak trucks for routing engine oil cooler lines, transmission oil supply hoses, and hydraulic steering circuits. The fitting features a precision‑machined body with a captive ferrule and compression nut that provides a secure, vibration‑resistant seal. Manufactured from high‑strength carbon steel with a zinc‑nickel coating, it withstands continuous exposure to hot oil, road salt, and mechanical stress.
Each WG9725550198 fitting is engineered to meet the original equipment pressure rating of 200 bar (2900 psi) for oil lines. The internal flow path is smooth and free of burrs, minimizing pressure drop and turbulence. The compression ferrule is designed to cold‑form onto the steel tubing during assembly, creating a permanent mechanical lock that resists pull‑out under extreme vibration. This design is field‑proven on millions of kilometers of highway and off‑road operation.
Using the correct OEM WG9725550198 fitting is essential because aftermarket fittings may have incorrect thread dimensions or inferior ferrule designs that lead to leaks or line failure. A leaking oil line can cause engine damage, fire hazard, or loss of steering assist. Genuine parts guarantee that the connection meets the same stringent quality standards as the original factory installation.
Specifically engineered for 16 mm OD, 2 mm wall steel tubing. Compression ferrule and nut provide a leak‑proof seal that outlasts the life of the hose.
Rated for 200 bar working pressure, 400 bar burst pressure. Suitable for engine oil, transmission fluid, and hydraulic oil applications.
Zinc‑nickel plating with topcoat provides >480 hours salt spray resistance. Prevents rust and seizing of threads, simplifying future disassembly.
Allows tight routing around chassis components. Reduces hose stress and eliminates sharp bends that can cause flow restriction or kinking.
The WG9725550198 elbow fitting is used on SINOTRUK Sitrak C7H, T7H, and A7 series trucks equipped with MC13 or MC11 engines. It connects the engine oil cooler to the oil filter housing, the transmission oil lines to the radiator, and power steering oil cooler circuits. It is also found on certain HOWO models that share the same oil line architecture. The fitting is designed for use with seamless steel tubing (DIN 2391) of 16×2 mm dimensions.
Common failure points in oil systems are often traced to loose or corroded fittings. Replacing a damaged or leaking WG9725550198 fitting during routine maintenance prevents fluid loss and potential engine damage. The fitting’s 90° angle allows routing in tight engine compartments, reducing the need for long, unsupported hose sections. It is compatible with all standard SAE and metric hydraulic fluids, including engine oil, automatic transmission fluid (ATF), and power steering fluid.
For fleets, keeping a stock of WG9725550198 fittings ensures quick repairs when oil leaks occur. The fitting is sold individually and can be reused if the ferrule is replaced (the ferrule is a single‑use component). Always inspect the mating tube for damage; if the tube is scored or corroded, replace the entire line to ensure a proper seal.
| Parameter | Specification |
|---|---|
| OEM Part Number | WG9725550198 |
| Product Name | Pipe Fitting (Connects Oil Line 16X2 Elbow) |
| Brand | SINOTRUK Sitrak (Genuine OEM) |
| Tube Connection Size | 16 mm OD x 2 mm wall |
| Fitting Angle | 90° (elbow) |
| Thread Type (Port Side) | M22 x 1.5 metric fine (external) |
| Material | High‑strength carbon steel (C45E) |
| Surface Finish | Zinc‑nickel plating + clear topcoat |
| Corrosion Resistance | >480 hours salt spray (ASTM B117) |
| Working Pressure | 200 bar (2900 psi) |
| Burst Pressure | ≥400 bar (5800 psi) |
| Temperature Range | -40°C to +150°C |
| Hex Size (Nut) | 24 mm |
| Installation Torque (Nut) | 30–35 Nm (on tube side) |
| Application | Sitrak C7H / T7H / A7 engine oil, transmission oil, power steering lines |
* Always use new tubing and clean the inside of the fitting before assembly. Torque values are for clean, lubricated threads. Do not overtighten.
Installing the WG9725550198 fitting requires attention to detail. First, cut the steel tubing squarely using a tube cutter. Deburr the inside and outside of the tube with a deburring tool to remove any sharp edges that could damage the ferrule or seal. Slide the compression nut and ferrule onto the tube, then insert the tube into the fitting body until it bottoms out. Tighten the nut by hand, then use a 24 mm wrench to torque to 30‑35 Nm. For systems with high vibration, a second tightening after the first heat cycle may be required.
Routine inspection of oil line fittings should be part of every preventive maintenance interval. Look for signs of oil wetness around the fitting, which indicates a leak. If the fitting has been disturbed, it is advisable to replace the ferrule and nut, as the compression ferrule cold‑forms to the tube and cannot reliably seal again after loosening. The WG9725550198 fitting body is reusable provided it is not damaged, but the compression components are single‑use.
For fleet maintenance, keep a supply of replacement ferrules and nuts specifically for this fitting. When replacing a damaged line, always install a new WG9725550198 fitting to ensure a leak‑free connection. Clean the threaded port on the engine or transmission component with a thread chaser before installation to prevent cross‑threading. After assembly, start the engine and inspect for leaks under operating pressure.
Aftermarket hydraulic fittings often use lower‑grade steel that can corrode internally and fail under pressure. The ferrule in generic fittings may not compress properly, leading to leaks that develop over time. Genuine WG9725550198 fittings are manufactured to precise tolerances, with a ferrule geometry optimized for 16×2 tubing. The zinc‑nickel coating provides superior protection against road salt and moisture, preventing the fitting from seizing to the tube or port.
The cost of an oil leak can be substantial: lost fluid, environmental cleanup, and potential engine damage from low oil pressure. A single failed fitting can cause hours of downtime. Genuine OEM fittings eliminate the risk of premature failure and ensure that repairs last as long as the original components. For fleets, standardizing on genuine WG9725550198 fittings reduces the total cost of ownership through fewer repeat repairs and extended component life.
When you choose genuine Sinotruk Sitrak parts, you receive a component that has been validated on the same trucks you operate. The fitting’s pressure rating, thread dimensions, and corrosion resistance are all verified to meet the original equipment requirements. Trust the quality that has been proven in millions of kilometers of service.
The WG9725550198 Pipe Fitting (Connects Oil Line 16X2 Elbow) is an essential component for maintaining leak‑free oil circuits on SINOTRUK Sitrak trucks. Its robust construction, high‑pressure capability, and corrosion‑resistant finish ensure long service life and reliable performance. Choose genuine parts to protect your engine, transmission, and power steering systems from fluid loss and premature wear.