The Honda F10A is a 997 cc, inline‑four naturally aspirated petrol engine produced between 1981 and 1986. It features a single overhead camshaft (SOHC) valvetrain and a carbureted fuel system, engineered for compact utility vehicles. Peak output is 55 PS (40 kW) at 5,500 rpm and 77 Nm of torque at 3,500 rpm, providing dependable low — RPM performance for light commercial use.
Fitted primarily to the Honda Acty (HA1, HA2 chassis) and Street (HA3), the F10A was designed for dri…
Honda
Production years 1981–1986 meet Japanese 1978 Emissions Standards (MLIT Type Approval #MLIT/HONDA-F10).
The Honda F10A is a 997 cc inline‑four naturally aspirated petrol engine engineered for kei-class vans and trucks (1981-1986). It combines SOHC architecture with a carbureted fuel system to deliver rugged, low-stress performance. Designed to meet Japanese 1978 emissions standards, it prioritizes reliability and economy for commercial use.
| Parameter | Value | Source |
|---|---|---|
Displacement | 997 cc | |
Fuel type | Petrol | |
Configuration | Inline‑4, SOHC, 8‑valve | |
Aspiration | Naturally Aspirated | |
Bore × stroke | 66.0 mm × 73.0 mm | |
Power output | 40 kW (55 PS) @ 5,500 rpm | |
Torque | 77 Nm @ 3,500 rpm | |
Fuel system | Carburetor (Keihin) | |
Emissions standard | Japanese 1978 Emissions Standards | |
Compression ratio | 9.0:1 | |
Cooling system | Water‑cooled | |
Turbocharger | None | |
Timing system | Chain-driven | |
Oil type | Refer to vehicle handbook / manufacturer specification | |
Dry weight | 105 kg |
The Honda F10A was used across Honda's HA platforms with transverse mounting. This engine received platform-specific adaptations-reinforced engine mounts in the Acty Truck-and featured a unique carburetor jetting for altitude compensation. All adaptations are documented in OEM technical bulletins.
Engine Finders UK Ltd, which operates EngineCode.uk, can pass your enquiry to engine suppliers in the UK. The service is for vehicles in the United Kingdom, with UK delivery or fitting. This is a commercially connected service, and sending an enquiry does not confirm diagnosis or compatibility.
Diagnostic reminder: If a technician has recommended replacing the engine, you can send an enquiry to engine suppliers in the UK. Confirm the diagnosis first: an engine-code record does not diagnose a fault.
The F10A's primary reliability risk is distributor drive gear wear, with elevated incidence in vehicles with neglected oil changes. Honda SIB 82-008 identifies the gear as a common failure point, while carburetor maintenance remains critical for smooth operation. Extended oil intervals and use of incorrect viscosity make ignition system longevity and fuel system integrity critical.
Analysis derived from Honda technical bulletins (1981-1986) and Japanese MLIT failure statistics (2015-2023). Repair procedures should follow manufacturer guidelines.
The most common questions about engine codes, what they mean, how to find them and how this database works
The F10A is renowned for its simplicity and durability. Its main concerns are distributor drive gear wear and carburetor maintenance. With regular oil changes using the correct specification and timely carburetor servicing, these engines can easily surpass 200,000 km. Its robust chain-driven timing system is a significant reliability advantage.
The most common issues are distributor drive gear wear (causing misfires and timing issues), carburetor clogging causing poor running, exhaust manifold gasket leaks producing a ticking noise, and timing chain slack causing rattling noises at idle.
The F10A was used in the first-generation Honda Acty van (HA1, HA2), Acty truck (HA1, HA2), and Street (HA3) from 1981 to 1986, powering these kei-class commercial vehicles.
Yes, the F10A can be mildly tuned. Basic modifications like a performance air filter and exhaust can yield small gains. More significant power increases typically require carburetor re-jetting, performance camshafts, and head work. Its simple design makes it a popular candidate for kei truck enthusiasts.
Fuel economy is excellent for its era and application. Expect around 6.5 L/100km (43 mpg UK) in mixed driving for a manual transmission model. Careful highway driving can see figures closer to 5.0 L/100km (56 mpg UK), making it very economical for commercial use.
No. The F10A is a non-interference engine. This means if the timing chain breaks, the pistons will not collide with the open valves, preventing severe internal engine damage. While a broken chain will stop the engine, it typically avoids catastrophic failure.
Honda recommends 10W-30 or 10W-40 engine oil meeting their specifications. Using a high-quality mineral or semi-synthetic oil is recommended. Oil should be changed every 5,000 km or 6 months to ensure the engine, particularly the distributor drive, operates reliably.
Comprehensive technical documentation and regulatory references
EngineCode.uk is operated by Engine Finders UK Ltd. It provides engine-reference information and an optional commercial enquiry service. It is not an official manufacturer website. Check the record's sources and confirm vehicle-specific details before relying on it for parts, repairs or replacement.
Our editorial standard prioritises relevant manufacturer documentation and official regulatory sources. The sources and verification status for a record should be checked alongside the data.
A statement is not verified merely because a source is listed. Where supporting evidence is missing or conflicting, the record should identify that limitation. Please report unsupported or inconsistent information.
Transparency in gaps
A missing or unverified value does not mean the manufacturer has withheld it. We distinguish information not yet verified, information not available to us, and information explicitly not disclosed by the source.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
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.
Records are subject to review and correction. Source links, dates and verification notes should be read with the technical information. Our Editorial and Sourcing Policy explains our standards and review process.
Found an error or missing source? Report a problem with this page. Include the field or statement concerned and a supporting source if available. You can also email corrections@enginecode.uk.
Copyright and permissions
Images and other material may be protected by copyright. Attribution does not by itself grant permission to reuse material. If you believe material on this site infringes your rights, contact copyrights@enginecode.uk with the page URL and details of your claim. We will review the material and take appropriate action.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
Our Privacy Policy explains how Engine Finders UK Ltd uses information from visits, vehicle lookups, enquiries and messages. Our Cookie Policy explains cookies and similar technologies and how to change your choices.
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.
Ownership and commercial services
EngineCode.uk is owned and operated by Engine Finders UK Ltd. Alongside our reference content, we offer an optional replacement-engine enquiry service through Engine Finders and may identify relevant services provided by businesses connected with us. These commercial connections are disclosed. Using an enquiry service is not required to read our reference content.
Engine Finders UK Ltd operates this website. Our optional enquiry service has a commercial purpose. Our Ownership and Commercial Disclosure explains the relationship between the reference website and that service. Participating suppliers pay a fee or subscription to participate on the network and receive quote requests.
Use this record as a starting point for identification. Specifications and vehicle applications may contain errors or omissions. Confirm the exact engine variant and compatibility using vehicle-specific documentation and a qualified supplier or technician.
All external links open in new tabs. Please verify current availability of resources.