LOADER Iran

Loader steering valve repair

The steering control valve in Volvo, Komatsu, and Hyundai loaders is a critical component of the hydraulic steering system, responsible for controlling oil flow and pressure to the steering cylinders. These valves are typically high-pressure, double-acting designs capable of withstanding operating pressures between 200 and 260 bar. Internally, they feature pistons, springs, and precisely machined housings with tolerances below 0.05 millimeters, enabling accurate oil flow control and precise steering shaft movement. Selecting the correct valve and maintaining the specified flow rate for each loader model is crucial to prevent vibration and premature wear of hydraulic components.

The mounting location of the steering valve is usually on the outlet path of the hydraulic pump, near the input shaft of the orbital steering unit. This position allows the valve to receive direct hydraulic pressure and transmit force accurately to the steering cylinders. The valve is connected to pressure and return lines using flange couplings and high-pressure-resistant O-rings. Improper alignment or installation can lead to leakage, reduced flow, and increased shaft vibration, shortening the lifespan of the hydraulic components.

The repair process for the steering valve involves disassembling the

Volvo loader L90 and L120 injection pump

The fuel injection pump for Volvo L90 and L120 loaders is a precision mechanical unit designed to deliver high‑pressure diesel consistently to six cylinders at exact timing. Typical delivery pressures range from 1600 to 2200 bar depending on engine load and RPM. The pump rotor and plunger assembly are CNC machined with tolerances below ±0.005 mm to maintain volumetric accuracy across all injection events. Flow metering is controlled by a calibrated governor that adjusts quantity within ±3% of target volume under varying engine speeds. Bearings and seals are made from hardened steel and fluorocarbon elastomers respectively, ensuring resistance to wear and thermal cycling up to 300 degrees Celsius. Each pump undergoes bench testing for injection timing, leakage, and pressure stability before installation, minimizing variations that reduce combustion efficiency or increase soot formation.

In operational environments, a well‑maintained injector pump on L90 and L120 loaders contributes directly to torque and fuel efficiency. Fuel delivery timing variance is typically kept within ±0.2 degrees crank angle to prevent pre‑ignition or detonation. Pump drive gears are helical cut to reduce noise and extend service life beyond 8000 engine hours with correct filtration. Precision

Volvo loader L90 and L120 connecting rod

The connecting rods used in the Volvo L90 and L120 loaders, particularly in the mid-to-late 2000s models equipped with the D6 series engines, possess a distinct design feature that sets them apart from conventional components: they utilize an eccentric, or offset, small end. Unlike a standard connecting rod where the centerline of the piston pin bore aligns perfectly with the centerline of the rod, Volvo engineered these rods with a slight offset. This design is implemented to reduce the side thrust exerted on the piston against the cylinder wall during the power stroke. By angling the force application more directly down the center of the crankshaft journal, this unique geometry minimizes friction and wear, contributing to the legendary durability and fuel efficiency of Volvo’s heavy-duty powertrains in these wheel loaders. order and buy Volvo loader L90 and L120 connecting rod from Iran.

Furthermore, the uniqueness of these connecting rods extends to their material composition and fracture-split manufacturing process. For the L120, which typically endures higher stress loads due to its larger size and application, the rods are often forged from high-strength micro-alloyed steel, differentiating them from potentially different metallurgy in the L90. Both models, however, ut

Volvo loader L90 and L120 starter

The starter system of the Volvo L90 wheel loader is engineered to deliver high cranking torque under heavy duty operating conditions. It typically uses a 24 volt electrical system with a heavy duty DC starter motor rated between 5.5 and 7.0 kW. The pinion drive engages a hardened steel ring gear with a module optimized for diesel compression ratios above 17:1. Cold cranking performance is stabilized through dual series connected batteries with a combined capacity near 180 to 220 Ah. The solenoid actuated engagement mechanism is designed for more than 30000 start cycles under normal maintenance conditions. Reinforced copper windings and high temperature insulation class F improve thermal resistance during repeated start attempts. You can order and buy volvo loader ignition starter from Iran.

In the Volvo L120 loader, the starter assembly is calibrated for higher displacement diesel engines generating greater internal resistance during compression. Output power commonly ranges from 7.0 to 9.0 kW to ensure reliable engine turnover in ambient temperatures down to minus 20 degrees Celsius. The overrunning clutch protects the armature from overspeed once the engine fires and exceeds starter rotational speed. Gear reduction architecture improves torque multiplication while reducing c

Volvo loader L90 and L120 liner kit

The engines of Volvo L90 and L120 loaders consist of a critical set of components that ensure optimal performance and stable power transmission. The cylinder block is made of gray cast iron with a compressive strength of 250–300 MPa and features internal cooling passages to withstand operating temperatures of 95–105°C. The crankshaft is alloy steel with heat-treated surfaces, a main journal diameter of 95–110 mm, and can handle torque up to 1,200 Nm. Pistons are forged aluminum with nickel coating, capable of withstanding cylinder pressures up to 160 bar. Connecting rods are Cr-Mo alloy steel with a core hardness of 35–40 HRC to resist fatigue from repeated impacts. Valves and camshafts have a surface hardness of 50 HRC, providing high wear resistance at engine speeds of 2,200–2,400 rpm.

The engine lubrication system includes a high-pressure oil pump delivering 180–200 liters per minute and 10–15 micron filters to maintain uniform flow and reduce friction. Water and oil radiators with a thermal capacity of 55–70 kW keep temperatures stable under heavy-duty conditions. The fully electronic fuel injection system operates at 1,600 bar, ensuring optimal consumption and producing 550–600 Nm of torque at 1,500–1,600 rpm. Bearings and bushings are ISO 492 standar

Volvo Loader L90 and L120 turbocharger

The Volvo L90 and L120 wheel loaders are equipped with turbocharged diesel engines designed for optimal performance in demanding construction and material handling applications. The Volvo L90, depending on the generation, features engines such as the TD61G or the more recent D6J, both of which are turbocharged to deliver gross power outputs ranging from 156 to 184 horsepower . Similarly, the Volvo L120 utilizes turbocharged powerplants like the TD73 KDE in the C-series or the advanced D8J in the H-series, generating between 208 and 272 horsepower . This forced induction system is critical for maintaining high torque at low engine speeds, providing the powerful breakout forces and fast hydraulic cycle times essential for productive loader operation .

Specific turbocharger models and their corresponding part numbers vary by engine type and model year. For earlier L90 models with the TD61 engine, a genuine Garrett T04E10 turbo with OEM part number 11033904 was commonly used . Later L120E models, powered by the D7E LA E3 engine, utilize a BorgWarner KKK S200G turbocharger identified by part numbers 1270-970-0016 and 04294367 . The newer L90H and L120H generations, featuring Volvo D6J and D8J engines respectively, continue the legacy of turbocharged performance . The consistent eng

Volvo loader L90 and L120 wheel oil seal

The wheel oil seal in Volvo L90 and Volvo L120 is installed at the interface between the wheel hub and the front or rear axle housing. It is positioned outboard of the tapered roller bearings and inboard of the hub flange. Its primary function is to retain differential oil and prevent the ingress of dust, water, and abrasive particles. The inner diameter typically ranges from 110 mm to 160 mm depending on axle configuration. Seal width is generally between 15 mm and 25 mm. Lip materials are commonly NBR or FKM, with thermal resistance up to 120 degrees Celsius. Internal pressure is usually below 0.5 bar, while shaft peripheral speed can reach 8 m per second. The garter spring provides a consistent radial load of approximately 15 to 25 N.

From an engineering perspective, the wheel hub seal operates through controlled interference between the elastomeric sealing lip and a hardened shaft surface. The recommended shaft surface roughness is Ra 0.2 to 0.8 microns to minimize wear and heat generation. Contact surface hardness is typically 55 to 60 HRC to resist scoring and micro pitting. Bearing radial play exceeding 0.3 mm can accelerate leakage and reduce seal service life. Under heavy mining conditions, average seal durability ranges from 4000 to 8000 operating hours. Proper insta

Volvo loader L90 and L120 gasket

The hydraulic cylinder gasket in Volvo L90 and Volvo L120 is installed at the rod gland area of the cylinder head. It remains in direct contact with the chrome plated piston rod. The primary function is to prevent dust, mud, sand, and abrasive particles from entering the hydraulic cylinder. The inner diameter typically ranges from 70 mm to 120 mm depending on lift or tilt cylinder size. Cross section width is generally between 10 mm and 20 mm. Groove tolerance is commonly manufactured to H9 class for proper press fit. Maximum rod linear speed can reach 0.5 m per second. The wiping lip is designed with single or double lip geometry at approximately 15 degree contact angle for effective contaminant removal.

The Volvo loader cylinder wiper seal gasket is commonly manufactured from polyurethane PU with hardness between 90 and 95 Shore A. In specific applications, reinforced NBR compounds may also be used. Standard polyurethane operates within a temperature range of minus 30 to plus 100 degrees Celsius. PU provides significantly higher abrasion resistance compared to conventional rubber materials. Although the wiper seal is not pressure bearing, it must withstand oil splash exposure up to 5 bar. The piston rod surface roughness should be below Ra 0.4 microns to minimize wear. Prop

Volvo loader pressure relief valve

The oil pressure relief valve in Volvo L90 and L120 wheel loaders is designed to maintain hydraulic system pressure within the main circuit. It regulates oil pressure precisely between 210 and 280 bar to protect the hydraulic pump, lift cylinders, and tilt cylinders from overpressure damage. The valve features a high-pressure hydraulic design with spring elements of specific stiffness and a steel body resistant to wear. Installed directly in the main hydraulic line, either before or after the pump, it diverts excess oil to the reservoir when pressure exceeds the set limit, ensuring system safety. This functionality extends component lifespan and reduces maintenance costs, optimizing loader performance in heavy-duty operations.

For both L90 and L120 models, the relief valve uses the OEM part number VOE11703649 and operates effectively within an oil temperature range of -20 to 95 °C. The valve can handle volumetric flows between 150 and 200 liters per minute, matching system hydraulic demands. Accurate pressure control reduces hydraulic oscillations, stabilizes system response, and improves lift arm and bucket performance. Laboratory testing shows the valve maintains pressure within ±5% under peak load conditions. Proper installation and maintenance in line with Volvo standard

Volvo loader L90 and L120 hydraulic pump

The main hydraulic pump of the VOLVO L90 and L120 loaders plays a critical role in supplying fluid pressure to the movement circuits and control levers. This pump is a variable displacement axial piston type with precise pressure and flow control, delivering a maximum flow of approximately 180 liters per minute at 2000 RPM. It is mounted at the front of the engine on an intermediate bracket to provide the shortest hydraulic path to the reservoir and control valves. The normal operating pressure of the pump reaches around 250 bar and it integrates with a load-sensing system to supply only the required flow, minimizing energy loss. High pump efficiency reduces oil temperature and wear, ensuring stable performance under harsh working conditions.

The numerical specifications of the main loader pump for VOLVO L90/L120 include piston diameter, rotor swash angle, and volumetric efficiency, all engineered with precision. Its variable displacement allows the output flow to adjust according to mechanical load, preventing sudden pressure spikes. The pump is directly coupled to the engine crankshaft to minimize mechanical losses and system vibration. Its control system uses pressure sensors and the Volvo ECU to instantly adapt to engine speed and hydraulic load variations. These features

Komatsu Wheel Loader WA800-3

The Komatsu WA800-3 wheel loader is equipped with an SAA12V140E-3 diesel engine producing 690 horsepower at 2000 RPM. The engine displacement is 27.0 liters, delivering a maximum torque of 4300 N·m at 1400 RPM. The hydraulic system features a 900 L/min pump with 280 bar working pressure, controlling the boom, bucket, and frame. The frame is made of high-strength steel with a bending resistance of 12,000 N·m. The standard bucket has a capacity of 13 cubic meters and a lift height of 4.2 meters, capable of moving large volumes of heavy materials such as soil, sand, and rock. The hydro-mechanical transmission with 4 forward and 3 reverse gears allows precise speed control up to 40 km/h.

The operating weight of the loader is 130 tons, and its overall length is 14.8 meters, ensuring stability and maneuverability on rough terrain and challenging conditions. Front and rear axles feature independent differential locks with a load capacity of 50 tons. The cabin includes an ergonomic vibration-absorbing seat, air conditioning, and digital controls to enhance comfort and reduce operator fatigue. The dual-circuit hydraulic braking system and adjustable hydraulic steering provide precise control on slopes and rocky environments. Fuel consumption is approximately 140 liters per hour, an

Komatsu Wheel Loader WA600-3

The Komatsu WA600-3 wheel loader is equipped with an SAA6D140E-3 diesel engine producing 360 horsepower at 2000 RPM. The engine displacement is 14.0 liters, delivering a maximum torque of 1550 N·m at 1400 RPM. The hydraulic system features a 420 L/min pump with 250 bar working pressure, controlling the boom, bucket, and frame. The frame is made of high-strength steel with a bending resistance of 4800 N·m. The standard bucket has a capacity of 6.5 cubic meters and a lift height of 3.5 meters, capable of moving large volumes of heavy materials such as sand, soil, and rock. The hydro-mechanical transmission with 4 forward and 3 reverse gears allows precise speed control up to 40 km/h.

The operating weight of the loader is 45 tons, and its overall length is 11.2 meters, ensuring stability and maneuverability on rough terrain and challenging conditions. Front and rear axles feature independent differential locks with a load capacity of 20 tons. The cabin includes an ergonomic vibration-absorbing seat, air conditioning, and digital controls to enhance comfort and reduce operator fatigue. The dual-circuit hydraulic braking system and adjustable hydraulic steering provide precise control on slopes and rocky environments. Fuel consumption is approximately 50 liters per hour, and the

Komatsu WA470-6 wheel loader

The Komatsu WA470-6 wheel loader is equipped with an SAA6D107E-2 diesel engine producing 270 horsepower at 2000 RPM. The engine displacement is 10.5 liters, delivering a maximum torque of 1380 N·m at 1400 RPM. The hydraulic system features a 320 L/min pump with 245 bar working pressure, controlling the boom, bucket, and frame. The frame is made of high-strength steel with a bending resistance of 3750 N·m. The standard bucket has a capacity of 4.8 cubic meters and a lift height of 3.25 meters, capable of moving large volumes of heavy materials such as soil, sand, and rock. The hydro-mechanical transmission with 4 forward and 3 reverse gears allows precise speed control up to 38 km/h.

The operating weight of the loader is 29 tons, and its overall length is 10 meters, ensuring stability and maneuverability on rough terrain and challenging conditions. Front and rear axles feature independent differential locks with a load capacity of 13 tons. The cabin includes an ergonomic vibration-absorbing seat, air conditioning, and digital controls to enhance comfort and reduce operator fatigue. The dual-circuit hydraulic braking system and adjustable hydraulic steering provide precise control on slopes and rocky environments. Fuel consumption is approximately 46 liters per hour, and the f

Komatsu Wheel Loader WA470-5

The Komatsu WA470-5 wheel loader is equipped with an SAA6D107E-1 diesel engine producing 260 horsepower at 2000 RPM. The engine displacement is 10.5 liters, delivering a maximum torque of 1300 N·m at 1400 RPM. The hydraulic system features a 300 L/min pump with 230 bar working pressure, controlling the boom, bucket, and frame. The frame is made of high-strength steel with a bending resistance of 3500 N·m. The standard bucket has a capacity of 4.5 cubic meters and a lift height of 3.2 meters, capable of moving large volumes of heavy materials such as soil, sand, and rock. The hydro-mechanical transmission with 4 forward and 3 reverse gears allows precise speed control up to 38 km/h.

The operating weight of the loader is 28 tons, and its overall length is 9.8 meters, ensuring stability and maneuverability on rough terrain and challenging conditions. Front and rear axles feature independent differential locks with a load capacity of 12 tons. The cabin includes an ergonomic vibration-absorbing seat, air conditioning, and digital controls to enhance comfort and reduce operator fatigue. The dual-circuit hydraulic braking system and adjustable hydraulic steering provide precise control on slopes and rocky environments. Fuel consumption is approximately 45 liters per hour, and the f

Komatsu Wheel Loader WA480-5

The Komatsu WA480-5 wheel loader is equipped with an SAA6D107E-1 diesel engine producing 280 horsepower at 2000 RPM. The engine displacement is 10.5 liters, delivering a maximum torque of 1350 N·m at 1400 RPM. The hydraulic system features a 320 L/min pump with 240 bar working pressure, controlling the boom, bucket, and frame. The frame is made of high-strength steel with a bending resistance of 3700 N·m. The standard bucket has a capacity of 5 cubic meters and a lift height of 3.3 meters, capable of moving large volumes of heavy materials such as soil, sand, and rock. The hydro-mechanical transmission with 4 forward and 3 reverse gears allows precise speed control up to 38 km/h.

The operating weight of the loader is 30 tons, and its overall length is 10.1 meters, ensuring stability and maneuverability on rough terrain and challenging conditions. Front and rear axles feature independent differential locks with a load capacity of 14 tons. The cabin includes an ergonomic vibration-absorbing seat, air conditioning, and digital controls to enhance comfort and reduce operator fatigue. The dual-circuit hydraulic braking system and adjustable hydraulic steering provide precise control on slopes and rocky environments. Fuel consumption is approximately 48 liters per hour, and the fu