 | This article needs additional citations for verification. (May 2022) |
The Toyota 1HZ is a straight-six diesel engine developed and produced by Toyota Motor Corporation beginning in 1990. It continues to be offered in vehicles sold in countries with lax emissions regulations, and those sold by Toyota Gibraltar Stockholdings for organisations such as the United Nations.
| Toyota HZ engine | |
|---|---|
 A Toyota 1HZ engine installed in the Land Cruiser. | |
| Overview | |
| Manufacturer | Toyota Motor Company |
| Production | 1990–present |
| Layout | |
| Configuration | Straight-6 |
| Displacement | 4.2 L (4,164 cc) |
| Cylinder bore | 94 mm (3.70 in) |
| Piston stroke | 100 mm (3.94 in) |
| Cylinder block material | Cast iron |
| Cylinder head material | Cast iron |
| Valvetrain | SOHC with 2 valves per cylinder |
| Valvetrain drive system | Timing belt |
| Compression ratio | 22.4:1 |
| RPM range | |
| Max. engine speed | 4000 |
| Combustion | |
| Fuel system | Mechanical fuel injection |
| Fuel type | Diesel |
| Oil system | Wet sump |
| Cooling system | Water-cooled |
| Output | |
| Power output | 131 PS (129 hp; 96 kW) |
| Torque output | 285 N⋅m (29 kg⋅m; 210 lb⋅ft) |
| Chronology | |
| Predecessor | Toyota H engine |
The 1HZ generates more power and torque than the previous 2H diesel engine. Despite being 30 years old, the 1HZ still sees use in Land Cruiser J70 production worldwide with the exception of petrol-only markets, Euro 4, and Australian markets, where the 1GR-FE and 1VD-FTV Turbo-Diesel is supplied respectively. A popular engine in the 80 series Land Cruiser, it replaced the 2H engine in the 80/85 series by 1990.
The 1HZ Toyota Landcruiser 4.2 litre (4164 cc) diesel inline 6-cylinder 12-valve SOHC (single overhead camshaft) is an indirect injection design, and delivers maximum power of 96 kW (129 hp) at 3800 rpm and maximum torque of 285 N⋅m (210 lbf⋅ft) at 2200 rpm.
The 5-cylinder variant of this engine is known as 1PZ.