Engine Piston 8-98041141-0 8980411410 For ISUZU 4HK1 6HK1 NPR NQR FSR FVR NPR75 FVZ75 — Verified OEM Direct Fit, 115mm STD Alfin Oil-Gallery Diesel Piston

The Engine Piston with OEM numbers 8-98041141-0 / 8980411410 is a verified direct-fit replacement for ISUZU 4HK1 (5.2L) and 6HK1 (7.8L) diesel engines. This piston is a critical reciprocating component responsible for converting combustion pressure into crankshaft rotation and managing thermal load within the cylinder.

The 4HK1 is a 5,193 cc water-cooled inline-4 OHC 16-valve turbocharged diesel engine, and the 6HK1 is a 7,790 cc inline-6 OHC 24-valve diesel engine. Both are widely used in ISUZU NPR, NQR, FSR, FVR, and FVZ series trucks from 2007 onward (E3/E4 emission standards). This piston is also compatible with ISUZU 700P and various construction equipment applications including Hitachi excavators.

• Dimensional Verification: Piston diameter 115 mm, compression height 66.10 mm, total height 96.60 mm, pin size 40 × 88 mm, combustion chamber 62 mm, ring grooves 3T × 2.5 × 4 mm — verified against OEM drawing specifications for the 4HK1/6HK1 platform.
• Material & Construction: Manufactured from cast iron / aluminum alloy with Alfin insert for ring-land reinforcement, oil cooling gallery construction, and precision-machined surfaces for reliable performance under sustained diesel combustion loads.
• Weight Verified: 1,480 g net weight per ISUZU parts catalog specification.
• OEM Cross-Reference Verified: Replaces 8-98041-141-0, 8-98041141-0, 8980411410, 8-98041141, 8-98041-141-2, 8980411412, 8-98041-141-1, 8980411411, 8-98041062-0, 8980410620. International brand cross-references include 8976028000 (Knecht/Mahle), P30490 (SAKURA), 055-02-0008 (Zevs), EPNS1923, EPNS1913, MV0866, 39679AGSTD.
• Multi-Platform Application: Confirmed compatible with ISUZU NPR, NPR-HD, NQR, NRR, NMR, FSR, FTR, FRR, FVR, FXR, and 700P trucks, as well as Hitachi/ZX series construction equipment equipped with 4HK1/6HK1 engines.

• Loss of engine compression: Worn or stuck piston rings reduce cranking pressure, causing hard starting and noticeable power loss under load.
• Excessive exhaust smoke (blue/white/black): Indicates oil passing rings or incomplete combustion — a top-end refresh often resolves it.
• Increased oil consumption: Glazed bores or tired ring packs allow oil to enter the combustion chamber, raising operating costs.
• Piston scoring or scuffing: Visible skirt wear or liner wall scoring caused by thermal expansion, insufficient lubrication, or overheating — requires immediate replacement to prevent catastrophic engine failure.
• Knocking or tapping noise: Piston slap or bearing wear requires inspection before further engine operation.

Confirmed Fitment Sources: eBay fitment data confirms compatibility with ISUZU FTR, FVR, FXR, NPR, NPR-HD, NQR, and NRR trucks equipped with the 4HK1 5.2L and 6HK1 engines from 2007–2010. OEM parts catalogs confirm application across FR/FS/FT series vehicle models.

Manufacturing conforms to ISO/TS16949 quality management system standards. Each unit undergoes 100% quality inspection before packaging.

1. Verify fitment: Confirm piston diameter (115 mm), compression height (66.10 mm), and ring groove dimensions (3T / 2.5 / 4.0 mm) against removed OEM piston.
2. Check piston-to-bore clearance: Measure cylinder liner bore and piston skirt diameter; compare against manual specification.
3. Ring installation: Install rings with correct orientation (top ring marking up); stagger ring end gaps at 120° intervals.
4. Pin & clip installation: Lubricate pin bore and install piston pin (40 × 88 mm); secure with new snap rings.
5. Connecting rod torque: Follow manual sequence — always confirm against the specific engine variant manual.
6. Liner protrusion: Verify liner protrusion meets specification before final assembly.

• Inspect compression and oil consumption at every 50,000 km or annually, whichever comes first.
• Replace piston rings and inspect pistons during any top-end overhaul.
• Monitor coolant condition and EGR system — the 4HK1/6HK1 common-rail system is sensitive to fuel quality and injector condition.
• Engine oil capacity: approximately 8.2 L (4HK1) / 15–17 L (6HK1) including filter.

• Standard packing: Neutral packaging / corrugated carton; wooden case available for bulk orders; color box and customer-branded packaging available.
• Set options: Piston only, or piston set with pin & clips — specify at inquiry.
• Suitable for: Engine rebuild workshops, fleet maintenance departments, spare parts distributors, and export wholesalers.
• Related parts available: Piston ring set (3T + 2.5 + 4.0 mm), cylinder liner kit (115 mm), piston pin (40 × 88 mm), clips, and full 4HK1/6HK1 overhaul kit.