Applicable Engine:
4JJ1 / 4JJ1-TC / 4JJ1-TCS / 4JK1 / 4JJ1 NEW
Applicable Brand:
ISUZU
Applicable Car:
D-MAX
Product parameters:
| Displacement | Fuel | Cylinder | Vale | Camshaft | Year |
| 2.5/3.0 |
Diesel
|
4 | 16 | 2 | 2004- |
Complete Cylinder Head
Complete Cylinder Head Assembly for Isuzu 4JJ1 3.0L DOHC Turbo Diesel Engine – 16 Valve CRDi
Introduction
Bare Cylinder Head Product NO.
| ML NO. | OEM NO. | REF NO. |
| MLG054A | 8973559708 8973559709 8982230192 8981756061 | 908350 |
| MLG054B | 8982230191 |
Product Description
This fully assembled cylinder head is engineered for the Isuzu 4JJ1 3.0L turbocharged diesel engine, a high-performance, fuel-efficient powerplant widely used in Isuzu D-Max, MU-X, NPR, NQR, N-Series trucks, and other commercial vehicles. The 4JJ1 engine features a DOHC 16-valve layout with common rail direct injection (CRDi)and is known for its durability in heavy-duty and off-road applications.
The cylinder head is manufactured from OEM-grade aluminum alloy, CNC-machined, pressure-tested, and built with all valve train components pre-installed, ready for quick and secure installation.
Technical Specifications
| Item | Specification |
|---|---|
| Engine Code | 4JJ1 |
| Engine Type | Inline-4, Turbocharged |
| Displacement | 3.0L (2999cc) |
| Fuel System | Common Rail Direct Injection (CRDi) |
| Valvetrain | DOHC – 16 valves |
| Turbocharger | Yes |
| EGR System | Yes (on most variants) |
| Cooling System | Water-cooled |
| Camshaft Drive | Timing gear and chain |
| Head Material | Cast aluminum |
| Compression Ratio | ~17.5:1 |
| Applications | Commercial & passenger diesel vehicles |
Included in Assembly
- Cylinder head casting
- Intake & exhaust valves
- Valve springs, retainers, and keepers
- Valve stem seals
- Camshafts (DOHC)
- Camshaft caps & journals
- Hydraulic lash adjusters / lifters
- Rocker arms or roller followers
- Pre-installed dowel pins and oil ports
All components are fully assembled and pressure-tested before shipment.
Required for Installation (Not Included)
| Item | Recommendation |
|---|---|
| Cylinder head gasket | Must replace |
| Cylinder head bolts | Must replace (torque-to-yield) |
| Intake / exhaust manifold gaskets | Replace |
| Timing gear set / chain | Inspect or replace |
| Rocker cover gasket | Replace |
| Fuel injector seals & washers | Replace |
| Fresh coolant & oil | Must replace |
| EGR gasket / pipe seals | Replace if equipped |
Compatible Vehicles
Used in a wide range of Isuzu diesel vehicles, including:
Passenger & Light Commercial
- Isuzu D-Max 3.0L CRDi
- Isuzu MU-X 3.0L Diesel
- Chevrolet Colorado 3.0L (some markets)
Commercial & Trucks
- Isuzu NPR 3.0
- Isuzu NQR, NKR, NLR series
- Isuzu ELF
- Isuzu N-Series trucks
- JMC or Chinese clones with 4JJ1 engine license
Compatibility may vary between Euro 3 / Euro 4 / Euro 5 emission setups and intercooler/EGR presence. Please confirm using VIN or OEM number.
OEM Part Numbers (Cylinder Head)
- 8973296730
- 8973296731
- 8973296732
- 8973296733
- 8980371770
- 8981851190
- 8981851180
(Variations by region, emissions, and EGR presence)
Common Engine Issues Solved
| Issue | Cause | How This Assembly Helps |
|---|---|---|
| Cylinder head cracks | Overheating, high load | New casting, pressure-tested |
| Valve seal failure | High mileage / oil burning | New valve stem seals installed |
| Compression loss | Warped head / valve seat wear | Precision-machined head surface & new seats |
| Camshaft wear / noise | Poor lubrication | New camshafts + journals installed |
| Injector seat erosion | Diesel carbon build-up | Pre-machined clean injector pockets |
Installation Guidelines
- Ensure cylinder block surface is flat and clean.
- Use new head gasket and bolts, torque in proper sequence.
- Align timing chain/gear correctly with camshaft/crankshaft marks.
- Reconnect fuel lines, EGR piping, and sensor plugs securely.
- Fill engine oil and coolant, and bleed air from the cooling system.
- Check valve clearance if required and verify compression.
- Perform idle test and leak inspection after engine startup.
Target Export Markets
The 4JJ1 engine is popular in:
- Asia: Thailand, Philippines, Vietnam, Indonesia
- Middle East: Iraq, UAE, Saudi Arabia, Iran
- Africa: Kenya, Nigeria, South Africa, Ghana
- South America: Peru, Ecuador, Chile
- Oceania: Australia, Papua New Guinea
Used by:
Engine rebuild workshops
Commercial truck fleets
Diesel repair garages
Parts distributors and dealers