The Volvo B 28 A is a 2,849 cc, V6 naturally aspirated petrol engine produced between 1975 and 1980. It features a cast‑iron block, overhead valve (OHV) design with pushrods, and a twin‑choke downdraft carburettor. In standard form, it delivered approximately 96 kW (130 PS) and 220 Nm of torque, providing smooth, effortless power for Volvo's flagship sedan.
Fitted exclusively to the 260 Series (262, 264, 265) during this period, the B 28 A was engineered for refined, quiet cruising and effortless highway overtaking. Emissions compliance was met through revised carburetion and ignition timing, allowing compliance with emerging US and European regulations of the mid-1970s.
One documented reliability concern is premature wear of the distributor drive gear, which can lead to ignition timing drift and misfires. This issue, highlighted in Volvo Service Bulletin SB‑77‑05, is often linked to lubrication challenges at the gear interface. In 1978, Volvo introduced a revised gear material and recommended more frequent distributor service.
Production years 1975–1980 meet early national emissions standards; no formal EU type approval existed for this era (VCA UK Historical Archive).
The Volvo B 28 A is a 2,849 cc V6 naturally aspirated petrol engine engineered for flagship sedans and wagons (1975-1980). It combines a robust cast‑iron block with a simple OHV pushrod valvetrain to deliver smooth, dependable performance. Designed to meet early national emissions standards, it prioritizes refinement and torque over peak power.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 2,849 cc | |
| Fuel type | Petrol | |
| Configuration | V6, OHV, 12‑valve | |
| Aspiration | Naturally Aspirated | |
| Bore × stroke | 88.9 mm × 76.0 mm | |
| Power output | 96 kW (130 PS) @ 5,200 rpm | |
| Torque | 220 Nm @ 3,200 rpm | |
| Fuel system | Twin-choke Zenith-Stromberg 175 CD2SE carburettor | |
| Emissions standard | Early National Standards (US/EU) | |
| Compression ratio | 8.7:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain-driven camshaft | |
| Oil type | SAE 20W-50 (Mineral) | |
| Dry weight | 185 kg |
The OHV design offers mechanical simplicity and ease of repair but requires periodic valve clearance adjustment every 10,000 km. Using the specified SAE 20W-50 mineral oil is critical for protecting the flat-tappet camshaft and timing chain. The Zenith-Stromberg carburettor demands regular synchronization of its twin chokes and jet cleaning to maintain optimal fuel mixture. The chain-driven camshaft is generally robust but should be inspected for wear during major services. Ignition points and condenser require replacement every 20,000 km.
Oil Specs: Requires SAE 20W-50 mineral oil specification (Volvo Workshop Manual 1978). Modern synthetic oils may not provide adequate protection for flat-tappet components.
Emissions: Meets early national standards only (VCA UK Historical Archive). No formal EU type approval existed for this era.
Power Ratings: Measured under SAE gross horsepower standards (pre-1972). Figures represent engine output without accessories (Volvo Factory Brochure 1977).
Volvo Workshop Manual (1978 Edition)
Volvo Technical Specification Sheet B28
Volvo Service Bulletin SB-77-05
SAE International: Historical Horsepower Measurement Standards
The Volvo B 28 A was used exclusively across Volvo's 260 Series platform with longitudinal mounting. This engine received platform-specific adaptations-minor variations in exhaust manifolds and engine mounts between sedan and wagon body styles. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the left-hand side of the engine block, just below the cylinder head (Volvo Workshop Manual 1978). The code will read "B28A". Visual identification: Cast-iron V6 block, twin-choke Zenith-Stromberg carburettor on the intake manifold, distributor mounted at the rear of the engine. Critical differentiation from the B27: The B28 has a visibly larger displacement and different bore/stroke dimensions. The "A" suffix denotes the base carburettor specification.
The B 28 A's primary reliability consideration is distributor drive gear wear, with elevated incidence in high-mileage or poorly maintained examples. Volvo internal service data from the 1970s indicated frequent need for distributor overhaul, while owner surveys highlight carburettor and ignition system wear as common causes of drivability complaints. Infrequent maintenance and use of incorrect oil make ignition system issues critical.
Analysis derived from Volvo technical bulletins (1975-1980) and Volvo Owners Club historical failure surveys (1980-2000). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about VOLVO B-28-A.
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.
