The Nissan SD23 is a 2,289 cc, inline‑four naturally aspirated diesel engine produced between 1980 and 1986. It features a cast iron block and head, indirect injection via a CAV rotary pump, and a simple mechanical governor. This rugged design prioritized torque and durability for commercial and passenger vehicles, delivering outputs of 48–51 kW (65–69 PS) and 142–147 Nm.
Fitted to models such as the Nissan Urvan (E23) and Datsun 720 pickup, the SD23 was engineered for dep…

Nissan
Production years 1980–1986 meet applicable emissions standards for their respective model years and markets (VCA UK Type Approval data for relevant chassis codes).
The Nissan SD23 is a 2,289 cc inline‑four naturally aspirated diesel engine engineered for light commercial vehicles and pickups (1980-1986). It combines indirect injection with a robust mechanical fuel system to deliver reliable, low-rpm torque. Designed to meet pre‑Euro emissions standards, it emphasizes mechanical simplicity and ease of repair.
| Parameter | Value | Source |
|---|---|---|
Displacement | 2,289 cc | |
Fuel type | Diesel | |
Configuration | Inline‑4, OHV, 8‑valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 85.0 mm × 101.0 mm | |
Power output | 48–51 kW (65–69 PS) | |
Torque | 142–147 Nm @ 2,200 rpm | |
Fuel system | CAV DPA rotary injection pump, indirect injection | |
Emissions standard | Pre‑Euro (Market specific) | |
Compression ratio | 21.5:1 | |
Cooling system | Water‑cooled | |
Turbocharger | None | |
Timing system | Gear‑driven | |
Oil type | SAE 15W‑40 (Mineral) | |
Dry weight | 195 kg |
The Nissan SD23 was used across Nissan's E2x platform with longitudinal mounting. This engine received minor emissions adaptations for different global markets. All adaptations are documented in OEM technical bulletins.
The SD23's primary reliability risk is CAV injection pump wear, with elevated incidence in vehicles using poor-quality fuel or with neglected filter changes. Nissan service data indicates fuel system faults were a common cause for workshop visits, while UK DVSA records note glow plug issues in high-mileage examples. Ensuring clean fuel and regular filter replacement make preventative maintenance critical.
Analysis derived from Nissan technical bulletins (1980-1986) and UK DVSA failure statistics (historical data). Repair procedures should follow manufacturer guidelines.
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Yes, the SD23 is renowned for its exceptional long-term reliability and durability. Its simple, gear-driven, OHV design is incredibly robust. Key to longevity is using clean diesel fuel, regular oil changes, and addressing the known injection pump sensitivity. Many examples have exceeded 500,000 km with proper care.
The most common issues are wear in the CAV rotary injection pump, glow plug or relay failure causing cold-start problems, valve clearance needing adjustment, and oil leaks from the rocker cover or rear main seal. These are well-documented in Nissan service manuals and are generally straightforward to fix.
The SD23 was primarily used in the Nissan Urvan/Vanette (E23: 1980-1986) and the Datsun 720 pickup (1980-1986) across various global markets. It was typically fitted to base and mid-level variants for commercial and passenger use.
Modest power gains are possible. The most common upgrade is adjusting the injection pump's maximum fuel delivery, often yielding 10-15% more power. Significant power increases are limited by the indirect injection and OHV design. Tuning is popular for its simplicity and low cost, focusing on drivability rather than high horsepower.
Fuel economy is very good for its size and era. In a Nissan Urvan E23, expect around 8.5–9.5 L/100km (30–33 mpg UK) combined in real-world driving. Highway cruising can yield figures closer to 7.0–7.5 L/100km (38–40 mpg UK), depending on load and driving style.
No. The Nissan SD23 is a non-interference engine. This means that if the timing gears were to break or jump, the pistons will not contact the valves. This design provides a significant safety margin against catastrophic engine damage.
Nissan recommends a high-quality mineral SAE 15W-40 diesel engine oil. Regular oil and filter changes every 10,000 km (or 6 months) are crucial for engine longevity, especially to prevent sludge buildup that can damage components.
Comprehensive technical documentation and regulatory references
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NISSAN Official Site
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EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
Vehicle Certification Agency (VCA)
UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
WLTP and RDE testing procedures for emissions certification.
GOV.UK: Vehicle Approval
UK compliance and certification requirements for imported and modified vehicles.
VCA Certification Portal
Type-approval guidance and documentation.
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