ISUZU Heat-resistant Steel Intake Valve with 45° Valve Seat Angle - OEM Standard Fit for 6BG1 6BD1 4BD1 Engines
Price:
Negotiable
MOQ:
20 PCS
Delivery Time:
5-8 Work Days
Brand:
YIMI
Product Description
ISUZU Intake Valve 1-12551139-0 1125511390 for 6BG1 6BD1 4BD1 Engine
OEM Standard Fit for FSR NPR Trucks & Hitachi Excavators
ISUZU Intake Valve 1-12551139-0 1125511390 Compatible with 6BG1 6BD1 4BD1 4BG1 Engines -- For FSR NPR NQR Trucks & Hitachi Excavators, OEM Standard Replacement
Product Overview
The ISUZU Engine Intake Valve with OEM numbers 1-12551139-0 / 1125511390 is a precision-engineered replacement designed for ISUZU 6BG1, 6BD1, 4BD1, 4BG1 series diesel engines. This valve is widely used in ISUZU FSR, NPR, NQR series trucks as well as Hitachi excavators and other construction machinery.
Working Principle
The intake valve is a vital part of the engine's valve train. During the intake stroke of a four-stroke engine, as the piston moves downward, the intake valve opens in advance and closes later (driven by the camshaft) to ensure more air/mixture enters the cylinder. The opening and closing timing must precisely match the piston position in the cylinder.
Failure Symptoms
⚠️ Inspect immediately if any of these occur:
| Symptom | Probable Cause |
|---|---|
| Noticeable power loss; poor acceleration; difficulty climbing hills | Intake valve poor sealing; reduced cylinder compression pressure |
| Rough idle; engine vibration; hard starting | Incorrect valve clearance or burnt valve; unstable intake air volume |
| Black smoke from exhaust (diesel) or increased fuel consumption | Insufficient intake air causing incomplete combustion; improper air-fuel ratio |
| Distinct "tapping" metallic noise from engine | Excessive valve clearance; or valve spring fatigue/fracture |
| Cylinder compression test reading below specifiion | Worn valve seat or bent valve stem; valve fails to seal completely |
Technical Specifiions
Material Standard: Heat-resistant steel with operating temperature range of -40°C to 800°C
Dimensional Precision: Valve stem diameter machining precision to ±0.005 mm; valve seat angle 45° or 30°
Hardness Specifiion: Valve seat induction-hardened to HRC 50-55; valve stem tip hardness HRC 55-60
Unit Weight: 0.14-0.15 kg per piece
???? Data Source Note: Material, hardness, and dimensional data are based on ISUZU 6BG1/6BD1 series engine factory workshop manual technical specifiions and general industry standards (ISO, JIS). Test reports available upon request.
| Part Number: | 1-12551139-0 1125511390 |
| Product Name: | Intake Valve |
| Car Model: | FSR NPR |
| Engine Model: | 6BG1 6BD1 4BD1 |
| Condition: | 100% Brand New |
Vehicle & Engine Compatibility
Primary Engine Appliions:
| Engine Model | Displacement | Primary Appliion |
|---|---|---|
| ISUZU 6BG1 | 6.5L | FSR/NPR trucks, Hitachi excavators |
| ISUZU 6BD1 | 5.8L | FSR/NPR trucks, construction equipment |
| ISUZU 4BD1 | 3.9L | NPR trucks, Hitachi excavators, JCB |
| ISUZU 4BG1 | 4.3L | Construction equipment, excavators |
Important Fitment Warnings:
- Intake vs. Exhaust Valve: This product is the Intake Valve with OEM 1-12551139-0. Exhaust valves use different part numbers.
- Valve Clearance Adjustment: After installation, valve clearance must be adjusted per ISUZU factory workshop manual specifiions.
- Set Replacement Recommended: Replace intake and exhaust valves together with valve stem seals and valve springs.
- Valve Seat Inspection: Always inspect valve seat wear when replacing valves.
- Timing System Confirmation: Verify engine timing marks are aligned before installation.
Features & Benefits
High-Quality Heat-Resistant Steel Construction: Excellent high-temperature strength and creep resistance; maintains structural integrity at 800°C.
Precision Machining Process: Valve stem diameter precision to ±0.005 mm; valve seat angle accurate to 45°.
Valve Stem Tip Hardened: Tip hardness HRC 55-60 for superior wear resistance.
100% Factory Quality Inspection: 100% dimensional, hardness, and visual inspection on every piece.
Broad OEM Cross-Compatibility: Replaces OEM numbers 1125511650 / 1-12551165-0.
One Part Number, Multiple Engine Models: Same valve fits 6BG1, 6BD1, 4BD1, 4BG1, 4BC2 engines.
Quality Control
| QC Item | Inspection Method | Acceptance Criterion |
|---|---|---|
| Valve stem diameter | Laser micrometer / Micrometer | ±0.005 mm |
| Valve seat angle | Special angle gauge / Profilometer | 45° ± 0.5° |
| Valve seat hardness | Rockwell hardness tester (HRC) | HRC 50-55 |
| Valve stem tip hardness | Rockwell hardness tester (HRC) | HRC 55-60 |
Installation & Maintenance
⚠️ IMPORTANT SAFETY NOTICE: Engine valves and cylinder head areas reach extremely high temperatures after operation. Allow the engine to cool completely before proceeding. Professional installation with specialized tools is strongly recommended.
Maintenance Schedule:
| Item | Interval | Notes |
|---|---|---|
| Valve clearance check/adjustment | Every 20,000-30,000 km | Check immediately if noise detected |
| Cylinder compression test | Every 50,000 km | Check valve sealing integrity |
| Valve assembly replacement | Engine overhaul (300,000-500,000 km) | Depends on operating conditions |
Packaging & Supply
| Packaging | Inner: Anti-rust bag / oil paper Outer: Standard export carton |
| Quantity per package | 6 pcs/set (for 6-cylinder engines) |
| Unit net weight | Approx. 0.14-0.15 kg |
| Target Customers | Truck parts wholesalers, repair shops, construction equipment parts suppliers |
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Company
Yimi (Guangzhou) Automotive Parts Co, Ltd
Location
Unit 1313, Building 5, Changsheng DDP Fashion Center, No. 17 Dachi Road, Tancun, Shijing Subdistrict, Baiyun District, Guangzhou City.
Contact Person
James