Cylinder Head Assembly 16-Valve DOHC High-Strength Alloy Cast Iron for ISUZU 4HK1 5.2L Common Rail Direct Injection Engine
The cylinder head assembly carrying OEM numbers 8-98008363-6 and 8-98018454-5 is a direct replacement for the ISUZU 4HK1 5.2L inline-four common rail diesel engine. Designed for medium-duty trucks including ISUZU NQR75, NPR5, and 700P series, as well as off-road equipment like Hitachi ZX200-3 and ZX240-3 excavators.
The 4HK1 is a 5,193 cc turbocharged diesel engine with bore and stroke of 115 mm × 125 mm, delivering 215 to 240 horsepower at 2,400-2,500 rpm and torque up to 452 lb-ft at 1,850 rpm. Operating with a common rail fuel injection system at up to 1,600 bar, the cylinder head is precision-manufactured to withstand extreme thermal and mechanical loads.
| Part Number | 8-98008363-6, 8-98018454-5 |
|---|---|
| Product Name | Cylinder Head Assembly |
| Car Model | ISUZU NQR75 NPR5 700P |
| Engine Model | ISUZU 4HK1 |
| Condition | 100% Brand New |
| Origin | China Mainland |
| Main Market | Middle East, Asia, Africa, South America, North America & Europe |
| Material | High-strength aluminum alloy & precision bearings |
| Cooling Type | Engine coolant circulation |
| Installation | Direct OEM replacement |
| Quality Standard | OEM equivalent / ISO quality control |
This ISUZU 4HK1 cylinder head assembly 8-98008363-6 directly replaces the factory head in the following configurations:
| Chassis / Model | Engine | Years | Notes |
|---|---|---|---|
| ISUZU NQR75 | 4HK1 | 2005-2010 | Medium chassis, 6-wheel |
| ISUZU NPR5 / NPR | 4HK1-TC | 2005-2015 | Most common N-series application |
| ISUZU 700P | 4HK1-TCN | 2005-2010 | North American and Asian markets |
| ISUZU NPR-HD | 4HK1-TCS | 2008-2016 | Heavy-duty variant, up to 11,700 kg GVWR |
| ISUZU NRR | 4HK1 | 2011-2016 | Low tilt and crew cab models |
| ISUZU FRR | 4HK1-TC / 4HK1-TCH | 2008-2016 | Medium chassis |
| ISUZU ELF | 4HK1 | 2006-present | Japanese domestic N-series |
| Hitachi ZX200-3, ZX240-3 | 4HK1 | 2006-2010 | Hydraulic excavator |
Cross-industry compatibility extends to:
- Hitachi ZX210L-3, ZX330 excavators
- Case CX210B, CX210C excavators
- Other OEMs using ISUZU 4HK1 base engine
- Direct OE Replacement - Manufactured to original equipment specifications using same engineering blueprints and material standards
- 16-Valve DOHC Configuration - Four valves per cylinder for improved volumetric efficiency, power output, and fuel economy
- High-Strength Alloy Cast Iron - Contains molybdenum, chromium, and nickel for elevated thermal stability and crack resistance
- Precision-Machined Combustion Chambers - Factory swirl pattern promotes thorough fuel-air mixing for complete combustion
- Integral Coolant Flow Optimization - Directs flow toward exhaust valve bridge to reduce risk of valve seat recession
- Hardened Valve Seats and Valve Guides - Powder metal alloy seats and precision-machined iron alloy guides with Viton stem seals
- Fully Assembled - Ready to Install - Reduces labor time by 2-3 hours compared to building from components
- Extensive Cross-Reference Coverage - Interchangeable with wide range of OEM part numbers
Each cylinder head batch undergoes comprehensive verification with IATF 16949 certification:
| QC Item | Verification Method |
|---|---|
| Material composition | Spectrographic analysis per casting batch |
| Hardness | Brinell hardness test on casting body |
| Combustion chamber volume | Measured on CMM – within ±0.5 cc of OE specification |
| Valve seat concentricity | Runout gauge measurement – ≤0.03 mm |
| Valve guide clearance | Air gauge measurement of ID |
| Valve stem protrusion | Dial gauge – within OE tolerance |
| Cylinder head flatness | Straight edge + feeler gauge across 6 orientations |
| Coolant passage integrity | Pressure decay test at 3 bar |
| Camshaft bearing bore alignment | CMM inspection – within 0.02 mm |
| Crack detection | 100% dye penetrant inspection (DPI) |
- Individual packaging: Sealed in anti-rust VCI bag, foam-lined carton
- Carton dimensions: 80 × 40 × 30 cm (approximate)
- Net weight: Approximately 70-80 kg (fully assembled)
- Gross weight (with packaging): Approximately 90-100 kg
- Master carton: Palletized – contact for specifics
- Lead time: 5-10 working days for stock orders
- Minimum order quantity: 1 piece (sample order available)
- Shipping: Sea freight (LCL/FCL) from Shanghai, Ningbo, Guangzhou ports
For complete top-end rebuilds, matching head gaskets (4HK1), head bolts (8-98008363-6 family), and valve adjustment shims are also available.
The ISUZU 4HK1 cylinder head assembly 8-98008363-6 (with supersession 8-98018454-5) is an OE-specification replacement for the 5.2L common rail diesel engine in NQR75, NPR5, 700P trucks, and Hitachi/Case excavators. Features 16-valve DOHC design, alloy iron casting, and precision-machined combustion chambers. IATF 16949 certified with batch traceability.
Order a sample unit today to verify fitment on your 4HK1 engine – the same head covers NQR, NPR, FRR, and off-road applications.
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