Nissan HR12DE Specifications
| Engine Model: Nissan HR12DE |
| Engine Type: 4-cycle inline 3-cylinder DOHC 12-valve CVTC liquid-cooled gasoline |
| Total Displacement: 73.1 cu.in (1.19 L) |
| Rated Engine Power: 75-80 Hp (56-59 kW) at 6000 rpm |
| Fuel System Type: Multi-point electronic fuel injection |
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The Nissan HR12DE is a 1.2-liter, inline-three,
naturally aspirated gasoline engine that belongs to Nissan’s HR-series
family, which includes HR10, HR12, and HR16 engines. Introduced in the
early 2010s, the HR12DE was designed as an extremely efficient,
lightweight, low-emissions powerplant for compact hatchbacks, small
sedans, and city crossover vehicles. It has been widely used in the
Nissan Micra (March), Nissan Note, Datsun GO/GO+, and several other
global market vehicles requiring high fuel efficiency and low running
costs.
The HR12DE emphasizes refinement, thermal efficiency, and emissions
performance. Its compact inline-three layout reduces weight and
mechanical friction, while advanced technologies - such as continuously
variable valve timing (CVTC), a lightweight aluminum block,
friction-reducing coatings, and optimized combustion chamber design -
allow it to achieve impressive fuel economy and smooth drivability.
Despite its small displacement and three-cylinder configuration, the
HR12DE provides adequate torque for city driving thanks to its
long-stroke geometry and intelligent valve-timing control.
As part of Nissan’s global powertrain strategy, the HR12DE replaces
older 1.2- to 1.4-liter naturally aspirated engines with a more
efficient and environmentally friendly alternative. It is engineered for
reliability, ease of maintenance, and low emissions while offering a
quiet and refined driving experience through advanced engine mount
tuning and low-vibration balancing.
The Nissan HR12DE is a water-cooled, inline-three, four-stroke gasoline
engine with a displacement of 1198 cmі (73.1 cu in). Bore is 78.0 mm
(3.07 in) and stroke is 83.6 mm (3.29 in), yielding a long-stroke
configuration that enhances low-rpm torque and overall efficiency. The
compression ratio is typically around 10.0:1 to 10.2:1 depending on
market and emissions calibration.
Maximum power output ranges from 75 to 80 horsepower (56 to 59 kW) at
approximately 6000 rpm. Maximum torque is typically 104 to 110 Nm (77 to
81 lb-ft) at around 4400 rpm. Idle speed is usually set at 750 ± 50 rpm.
The firing order is 1-2-3. The engine delivers smooth operation for a
three-cylinder unit thanks to optimized crankshaft design, lightweight
pistons, and NVH-focused engine-mount geometry.
The crankshaft is a forged steel unit with three crankpins and four main
bearings, designed to minimize friction and vibration. A
counterweighted, offset crankshaft layout reduces secondary vibration
typical of three-cylinder engines. Connecting rods are fracture-split
steel components, providing precise big-end cap alignment and high
durability.
Pistons are lightweight aluminum alloy with
low-friction skirt coatings and modified crown profiles that support
efficient combustion. Piston rings are low-tension designs to reduce
mechanical drag. The wrist pins float inside the connecting rods to
distribute wear and improve long-term durability.
The aluminum cylinder head houses dual overhead camshafts (DOHC)
operating four valves per cylinder - two intake and two exhaust - for a
total of 12 valves. Valve actuation is achieved by direct mechanical
bucket tappets or roller finger followers depending on sub-variant,
minimizing valvetrain mass and improving efficiency.
The HR12DE utilizes Nissan’s CVTC (Continuously Variable Valve Timing
Control) system on the intake camshaft, adjusting valve timing according
to engine load, temperature, and rpm. CVTC improves low-rpm torque,
high-rpm breathing, emissions performance, and fuel economy. Some
regional versions also feature CVTC on the exhaust camshaft.
Valve diameters:
- Intake valves: approx. 27 to 29 mm (1.06 to 1.14 in)
- Exhaust valves: approx. 23 to 25 mm (0.91 to 0.98 in)
The HR12DE features electronic multi-point fuel injection (MPI). An
in-tank electric pump supplies fuel to the fuel rail at regulated
pressure - typically 300 to 350 kPa (43 to 50 psi). Each cylinder has a
dedicated injector that atomizes fuel into the intake port for efficient
mixing.
Sensors used by the ECU include:
- Mass Air Flow (MAF) sensor
- Throttle Position Sensor (TPS)
- Engine Coolant Temperature Sensor (ECT)
- Crankshaft Position Sensor (CKP)
- Camshaft Position Sensor (CMP)
- Oxygen sensor(s)
- Intake Air Temperature Sensor (IAT)
- Manifold Absolute Pressure Sensor (MAP) on some variants
The throttle body is electronically controlled or cable-operated
depending on market. Idle speed is regulated by the ECU via an
electronic throttle plate or idle-air bypass control.
The HR12DE employs a full-pressure wet-sump lubrication system. A
trochoid-type oil pump mounted on the crankshaft delivers oil to the
crankshaft bearings, connecting rod journals, camshaft journals,
valvetrain components, and timing chain. The oil pump’s design minimizes
parasitic losses and contributes to overall engine efficiency.
Oil capacity ranges from 3.0 to 3.5 liters (3.2 to 3.7 US quarts).
Recommended oil viscosity is SAE 0W-20 or 5W-30 depending on market
temperature range and service requirements.
Oil pressure:
- 3000 rpm: 350–450 kPa (50–65 psi)
- Idle: > 70 kPa (> 10 psi)
The cooling system is a liquid-cooled, forced-circulation design using a
belt-driven water pump. Coolant flows through the block, head, radiator,
and heater core. The thermostat begins opening around 82°C (180°F) and
is fully open near 95°C (203°F).
Cooling system components include:
- Aluminum cross-flow radiator
- Electric cooling fan controlled by ECU
- Overflow reservoir
- Integrated coolant passages for rapid warm-up
- Exhaust valve cooling channels for durability
Coolant capacity is roughly 5.0 liters (5.3 US quarts).
| Intake and Exhaust Systems |
The induction system includes:
- Plastic air inlet duct
- Dry-paper air filter
- Resonator chambers to reduce intake noise
- Aluminum or molded composite intake manifold
- Electronic throttle body
The exhaust manifold is integrated into the cylinder head, reducing
warm-up time and improving emissions efficiency. Exhaust gases flow
directly into a close-coupled catalytic converter before passing through
additional downstream catalysts and mufflers. In some versions, EGR
(exhaust gas recirculation) is included.
| Ignition and Electrical System |
The HR12DE uses coil-on-plug ignition, eliminating plug wires and
improving spark precision. Each coil is individually controlled by the
engine’s ECU.
Spark plug specifications:
- Type: Iridium-tipped
- Gap: approx. 1.0 mm (0.039 in)
- Replacement interval: 40,000–60,000 km (25,000–37,000 miles)
The alternator typically outputs 80–110 amperes depending on vehicle
application. System voltage is 12 V DC. The starter motor is a
reduction-gear unit for reliable cold starts.
- Length: 520–550 mm (20.5–21.7 in)
- Width: 500–520 mm (19.7–20.5 in)
- Height: 620–650 mm (24.4–25.6 in)
Dry weight: 85–105 kg (187–231 lb), depending on accessory
configuration.
- Engine oil and filter: every 10,000–15,000 km (6000–9000 miles)
- Air filter: every 20,000 km (12,000 miles)
- Spark plugs: every 40,000–60,000 km
- Coolant: every 100,000 km (60,000 miles) or 5 years
- Drive belt: inspect every 20,000 km
- Fuel filter: typically lifetime tank filter; inspect approx. 120,000
km
- Compression: 1400–1800 kPa (203–261 psi), variation max 100 kPa (15
psi)
- Cylinder head bolts: 40 Nm (30 lb-ft) + 90° + 90°
- Connecting rod bolts: 20–25 Nm (15–18 lb-ft) + 70°
- Main bearing bolts: 50–60 Nm (37–44 lb-ft)
- Spark plugs: 20 Nm (15 lb-ft)
- Oil drain plug: 30 Nm (22 lb-ft)
- Intake manifold bolts: 20–22 Nm (15–16 lb-ft)
- Exhaust manifold/turbo bolts (NA/variant): 35–45 Nm (26–33 lb-ft)
The HR12DE is used in a wide range of
Nissan and Alliance vehicles, including:
- Nissan Micra / March (K12, K13)
- Nissan Note (E12 non-supercharged versions)
- Datsun GO and GO+
- Regional emerging-market sedans and hatchbacks
- Nissan NV100 Clipper (selected versions)
- Mitsubishi-branded kei derivatives in Japan (some variants)
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