Gear-driven Oil Pump Assembly with Integrated Pressure Relief Valve for Isuzu 4HK1 4HF1 Engine - OE Quality Auto Spare Parts

Premium-quality direct replacement engine lubrication component designed for Isuzu 4HK1 and 4HF1 diesel engines, commonly used in Isuzu NPR, NQR, ELF, and other medium-duty trucks.

Engine oil pump circulates pressurized oil to bearings, pistons, camshaft, and valve train. Ensures proper lubrication, cooling, and cleaning of engine components for Isuzu 4HK1/4HF1 diesel engines.

• OE Quality: Manufactured to Isuzu dimensional and material specifications for perfect fit and reliable oil pressure
• Precision Gears/Rotors: Hardened and ground to tight tolerances for consistent flow and minimal noise
• Integrated Pressure Relief Valve: Prevents over-pressurization at high RPM, protecting oil filter and seals
• Durable Housing: Corrosion-resistant cast iron or aluminum construction withstands engine heat and vibration
• High Flow Capacity: Delivers adequate oil volume for turbocharger cooling and piston jets under high load
• Direct Replacement: Matches OE mounting holes, drive gear interface, and oil passages
• Cost-Effective: Affordable alternative to genuine OEM without compromising reliability

This oil pump assembly is specifically designed for Isuzu 4HK1 and 4HF1 engines.

• ISUZU NPR (NPR66, NPR70, NPR71, NPR75, etc.)
• ISUZU NQR (medium-duty truck)
• ISUZU ELF (N-series)
• Other Isuzu commercial vehicles with 4HK1/4HF1 engines

Installation steps (overview):

1. Drain engine oil - remove oil pan and clean sealing surfaces
2. Remove old oil pump - unbolt from engine block. Note gasket or seal orientation
3. Clean mounting surface - remove old gasket material. Ensure no debris falls into the engine
4. Prime the new oil pump - fill with clean engine oil or pack with assembly lube to ensure immediate suction on startup
5. Install new pump - use new gasket or O-ring. Torque mounting bolts to specification (typically 20-30 Nm)
6. Reinstall oil pan - with new gasket or sealant. Torque pan bolts
7. Install new oil filter - pre-fill if possible
8. Refill with new engine oil - correct grade and quantity
9. Prime the lubrication system - disable fuel system and crank engine for 10-15 seconds until oil pressure light goes out
10. Start engine - check oil pressure light goes off immediately. Inspect for leaks
11. Test drive - verify normal oil pressure and no unusual noise

• Material Verification: Housing and gear alloy composition tested
• Dimensional Inspection: Gear clearances, housing bore diameters, and mounting flange verified
• Flow/Pressure Test: Pump tested on a test bench for flow rate and pressure at specified RPM
• Relief Valve Test: Valve opening pressure verified
• Wear Test: Sample pumps run for durability cycles
• Visual Inspection: 100% checked for casting defects, burrs, or contamination
• Packaged Safely: Pump sealed in plastic bag, boxed with foam to protect ports and drive gear

Neutral export packing or customized packaging available. Carton or wooden case for safe transportation. Fast delivery for stock items. Shipping by Express Air or Sea.