Valve Insert Seat 8-98028874-0 8980288740 Intake For ISUZU FVR34 6HK1 4HK1 Diesel Engine

The Valve Insert Seat (OEM Numbers: 8-98028874-0 / 8980288740 / 8943958880 / 8-94395888-0) is a premium-quality, direct replacement engine valve train component designed specifically for ISUZU FVR34 series heavy-duty trucks equipped with 6HK1 and 4HK1 diesel engines. This precision-engineered intake valve seat insert — also known as a valve seat ring or valve insert — is press-fitted into the cylinder head and provides a durable, heat-resistant sealing surface for the intake valve to seat against. When the valve closes, it contacts the seat insert to form a gas-tight seal, which is essential for maintaining proper compression, preventing combustion gas leakage, and ensuring efficient engine breathing.

Function: The valve insert seat provides a hardened sealing surface for the intake valve to seat against, ensuring proper combustion chamber sealing, efficient airflow, and reliable engine compression in ISUZU diesel engines.

• OE Quality: Manufactured to strict ISUZU dimensional and material specifications for perfect fit and function.
• High-Grade Heat-Resistant Alloy: Cobalt-based or high-nickel chromium alloy resists pitting, deformation, and valve recession under extreme thermal cycling.
• Precision 45° Face Angle: Exact face angle ensures proper valve sealing and optimal combustion chamber integrity.
• 38mm Outer Diameter: Precision-machined to exact tolerances for a secure press-fit into the cylinder head bore.
• Enhanced Durability: Heat-resistant and corrosion-resistant material composite provides long-lasting performance under high combustion temperatures.
• Restores Valve Sealing: Eliminates compression loss, misfire, and poor engine performance caused by a worn or damaged seat insert.
• Improves Engine Efficiency: Proper valve sealing ensures optimal compression, combustion efficiency, and fuel economy.
• Direct Replacement: Matches OE seat dimensions and mounting configuration for simple installation.
• Long Service Life: Engineered for heavy-duty commercial and industrial diesel engine applications.
• Wide Compatibility: Suitable for ISUZU trucks and a wide range of construction and industrial equipment using 6HK1 and 4HK1 engines.
• Cost-Effective Repair: Affordable replacement that prevents costly valve and cylinder head damage.

This valve insert seat is specifically designed for ISUZU vehicles and equipment using the 6HK1 and 4HK1 engine family. Common applications include:

• ISUZU FVR34 (Heavy-Duty Trucks)
• ISUZU FTR, FSR, FSS, FRR, FVZ (Heavy-Duty Trucks)
• ISUZU FVM, FVW, GVR (Heavy-Duty Trucks)
• ISUZU 700P (Medium-Duty Trucks)
• ISUZU ELF (Light-Duty Trucks)
• ISUZU NPR75, NQR71, NQR75, NQR90 (Medium-Duty Trucks)
• ISUZU NNR, NPS (Light-Duty Trucks)

• Hitachi Excavators: ZX200, ZX210, ZX240, ZX250, ZX330, ZX350, ZX360, ZX370, ZX400, and more
• JCB Excavators: JS190, JS200, JS210, JS220, JS235, JS240
• Case Excavators: CX210B, CX230B, CX210C, CX235C, CX250C, CX300C, CX330C, CX350C, CX370
• Kobelco Excavators (as applicable)
• Hidromek Excavators: HMK200, HMK220, HMK300, HMK370
• Denyo Generators: DCA-125, DCA-180

• ISUZU 6HK1 — 7.8L Inline-6 Diesel
• ISUZU 6HK1-T / 6HK1-TC — Turbocharged Variants
• ISUZU 4HK1 — 5.2L Inline-4 Turbo Diesel
• Application: Heavy-duty trucks and construction equipment

Professional engine builder or mechanic installation is strongly recommended:

1. Ensure engine is cool — Allow the engine to cool completely before disassembly.
2. Disconnect battery — Always disconnect the negative terminal before working.
3. Remove cylinder head — Remove the cylinder head from the engine block to access the valve seats.
4. Remove valves — Use a valve spring compressor to remove the valve springs and valves.
5. Remove old valve seat insert — Use a valve seat puller or a suitable press to remove the old seat insert from the cylinder head. Alternatively, the seat can be machined out carefully.
6. Clean the seat bore — Thoroughly clean the valve seat bore in the cylinder head; remove carbon, oil, and debris.
7. Inspect the bore — Check the seat bore for wear, scoring, or damage; ream or replace the cylinder head if necessary.
8. Chill the new seat insert — For proper installation, chill the new valve seat insert in a freezer or with dry ice to slightly shrink it for easier press-fit.
9. Install the new valve seat insert — Press the new seat insert into the cylinder head bore using a proper driver and press until it is fully seated at the correct height. Ensure the smooth side of the attachment contacts the valve seat insert.
10. Grind/ream the seat — After installation, grind or ream the valve seat to achieve the proper contact width (2.5mm standard for intake valve) and concentricity with the valve guide.
11. Check contact pattern — Use marking compound to verify proper valve-to-seat contact pattern.
12. Inspect valve — Check the valve face and stem for wear or damage; replace if necessary.
13. Reinstall valves — Install the valves, valve springs, and retainers using a valve spring compressor.
14. Reinstall cylinder head — Install a new head gasket and reinstall the cylinder head; torque bolts to specification.
15. Start and test — Start the engine; check for proper operation, smooth idle, and no abnormal noise.
16. Road test / Operational test — Test the vehicle or equipment to verify proper engine performance and compression.

• Material Verification: Confirms high-grade heat-resistant alloy steel composition (cobalt-based or high-nickel chromium alloy) meets ISUZU strength and wear resistance specifications.
• Dimensional Inspection: Outer diameter (38mm), face angle (45°), and height verified within OEM tolerances.
• Surface Finish Inspection: Seat face checked for proper smoothness, flatness, and absence of pits or cracks.
• Hardness Testing: Seat material tested for proper hardness and resistance to valve recession.
• Heat Resistance Testing: Sample tested for performance across specified temperature range (-30°C to +320°C).
• Visual Inspection: 100% checked for cracks, machining defects, or surface imperfections.
• Packaged Safely: Protected with rust inhibitor and packaged to prevent damage during transit.

• 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