The Volvo B 23 A is a 2,316 cc, inline‑six naturally aspirated petrol engine produced between 1975 and 1984. It featured an overhead camshaft (OHC) design with a cast iron block and head, marking a significant evolution from the OHV B20. Output ranged from 96 kW (130 PS) to 103 kW (140 PS), with torque figures around 186–196 Nm, providing smooth and refined performance for Volvo's larger sedans.
Fitted primarily to the Volvo 240 Series (242/244/245) and 260 Series, the B 23 A wa…
Production years 1975–1984 meet US Federal or early Euro 1 standards depending on market and specification (EU Regulation (EC) No 715/2007 historical annex).
The Volvo B 23 A is a 2,316 cc inline‑six naturally aspirated petrol engine engineered for mid‑size and executive sedans (1975-1984). It combines a single overhead camshaft (SOHC) design with a robust seven-main-bearing crankshaft to deliver smooth, reliable performance. Designed to meet contemporary emissions standards, it relies on carburetion and EGR for compliance.
| Parameter | Value | Source |
|---|---|---|
Displacement | 2,316 cc | |
Fuel type | Petrol | |
Configuration | Inline‑6, SOHC, 12‑valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 88.9 mm × 62.5 mm | |
Power output | 96–103 kW (130–140 PS) | |
Torque | 186–196 Nm | |
Fuel system | Single downdraft carburetor (e.g., Zenith-Stromberg, Carter) | |
Emissions standard | US Federal / Early Euro 1 (market dependent) | |
Compression ratio | 9.0:1 – 9.3:1 | |
Cooling system | Water‑cooled | |
Turbocharger | None | |
Timing system | Chain-driven camshaft | |
Oil type | SAE 10W-40 (detergent, API SF/CC) | |
Dry weight | Approx. 185 kg |
The Volvo B 23 A was used across Volvo's 240/260 platforms with longitudinal mounting. This engine received minor updates during its production run, including revised camshaft profiles and carburetor specifications for different markets. All adaptations are documented in OEM technical bulletins.
The B 23 A's primary long-term reliability risk is camshaft lobe and follower wear, particularly in units with poor maintenance history. While formal failure statistics are unavailable for this vintage, enthusiast club data and workshop reports consistently cite cam wear, carburetor issues, and cooling system neglect as the most common causes for repair. Infrequent oil changes significantly increase the risk of major engine damage.
Analysis derived from Volvo technical bulletins (1975-1984) and aggregated data from Volvo enthusiast clubs and specialist workshops. Repair procedures should follow manufacturer guidelines where available.
The most common questions about engine codes, what they mean, how to find them and how this database works
The B 23 A is renowned for its smoothness and robust inline-six construction, making it fundamentally reliable if well-maintained. Its main vulnerability is camshaft lobe wear, which can be prevented with strict adherence to oil change intervals and using the correct specification. With diligent servicing, these engines can run reliably for hundreds of thousands of miles.
The most frequent issues are camshaft lobe/follower wear (often from poor oil maintenance), carburetor problems (wear, clogging), oil leaks from aged gaskets/seals, and cooling system failures (radiator corrosion, water pump failure). These are well-documented in vintage Volvo service literature and bulletins.
The B 23 A engine was used in the Volvo 240 Series (242, 244, 245) from 1975 to 1984 and the Volvo 260 Series (262, 264, 265) from 1975 until 1980. It was eventually replaced by fuel-injected variants like the B23E and the larger B230 engine.
Yes, within limits. Common upgrades include fitting a higher-flow carburetor, a performance exhaust manifold, and a free-flow exhaust system. More aggressive camshafts and higher compression pistons are also available. Significant power gains are possible, but the engine's age should be considered.
Fuel economy is modest by modern standards. Expect figures around 12-15 L/100km (18-23 mpg UK) in mixed driving for a car like the 244. This can vary significantly based on the specific carburetor, driving style, and vehicle condition.
No. The Volvo B 23 A is a non-interference (or 'free-wheeling') engine. If the timing chain fails, the pistons will not contact the valves, preventing catastrophic internal damage. This is a significant safety feature for a vintage engine.
For original specification, a high-quality detergent oil like SAE 10W-40 meeting API SF/CC standards is essential to protect the camshaft as per Service Bulletin #23A-02. Modern classic car oils with ZDDP additives are recommended for added protection against wear.
Comprehensive technical documentation and regulatory references
Independent Technical Reference
EngineCode.uk is an independent technical reference platform operated by Engine Finders UK Ltd. We are not affiliated with VOLVO or any other manufacturer. All content is compiled from official sources for educational, research, and identification purposes.
Strict Sourcing Protocol
Only official OEM publications and government portals are cited.
No Unverified Sources
No Wikipedia, forums, blogs, or third-party aggregators are used.
Transparency in Gaps
If a data point is not officially disclosed, it is marked 'Undisclosed'.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
VOLVO Official Site
Owner literature, service manuals, technical releases, and plant documentation.
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.
Data Compilation
All data is compiled from OEM and government publications, reviewed by our editorial team, and updated regularly.
Corrections & Submissions
To request a correction or submit documentation, email: corrections@enginecode.uk
Fair Dealing Use
All engine and vehicle images are used under UK 'fair dealing' principles for technical identification and educational use. Rights remain with their respective owners.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
GDPR Compliance
EngineCode.uk complies with UK GDPR. We do not collect personal data unless explicitly provided.
Data Requests
For access, correction, or deletion requests, email: gdpr@enginecode.uk
Trademark Notice
All trademarks, logos, and engine codes are the property of their respective owners. Use on this site is strictly for reference and identification.
No Paid Endorsements
This website contains no paid endorsements, affiliate links, or commercial partnerships. We do not sell parts or services.
Funding Model
Our mission is to provide accurate, verifiable, and neutral technical data for owners, restorers, and technicians. This site is self-funded.
All specifications and compatibility data verified against officialVOLVO documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed”.
All external links open in new tabs. Please verify current availability of resources.