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HistoryGeneral
History of the AC Aceca
The 1954 debut, the Bristol-engined transformation, and the end of production in 1963.
/history
ReferenceGuideEngineBodyGeneral
Parts and specialists
Who supplies parts and who works on the AC Aceca: the AC two litre six, the Bristol 100D2, the Ruddspeed 2.6, bodywork, trim and the shared parts you can buy off the shelf.
/parts-and-specialists
ReferenceGuideGeneral
Clubs, registers and your car's history
There is no AC heritage certificate. What exists instead: the AC Owners Club registers, the DVLA V765 scheme, the Bristol factory archive and the books worth owning.
/clubs-and-records
HistoryGeneral
What was the first hatchback car?
The competing claims of the Aston Martin DB2/4, the Renault 16 and the Traction Avant Commerciale, and the 1954 Aceca left off the lists.
/first-hatchback-car
ReferenceGeneral
Changelog, what has changed on this archive
A dated record of substantive changes: new pages, corrections of fact, restructuring and new photographs.
/changelog
HistoryGeneral
Thames Ditton and the AC Works
The Ferry Works at Thames Ditton, AC's home from 1911 to 1986, where every Ace and Aceca was hand-built.
/thames-ditton
The CarBodyGeneral
The Car, how the Aceca was built
Tojeiro tubular-steel chassis, a composite steel-tube-and-ash body frame, hand-formed aluminium panels, hatchback tailgate.
/the-car
The CarReferenceEngineGeneral
Variants, Aceca, Aceca-Bristol, Aceca 2.6
The three engine options across the range and the numbers of each built.
/variants
The CarEngineFuel
The AC-engined Aceca
The original AE-prefix Aceca on AC's 2.0-litre Light Six with triple SU carburettors.
/aceca-ac
The CarReferenceEngine
AC Bristol, the Bristol-engined AC cars
What 'AC Bristol' means: the Ace-Bristol, Aceca-Bristol and Greyhound, and the engine they share.
/ac-bristol
The CarEngineFuel
The Aceca-Bristol
The Bristol-engined BE-prefix Aceca, the transformation of the model.
/aceca-bristol
The CarReferenceEngineFuel
The Aceca-Bristol: The One to Have
Fitted with the legendary Bristol two-litre six, the Aceca-Bristol is the most celebrated, most capable, and most sought-after of all Acecas.
/aceca-bristol-detail
The CarEngine
The Aceca 2.6
The final RS-prefix Aceca on the Ruddspeed-tuned Ford Zephyr 2.6.
/aceca-26
The CarReferenceEngine
The AC Light Six Engine
John Weller's 1919 two-litre six: aluminium block, single overhead camshaft, in production until 1963.
/ac-engine
The CarReferenceEngine
The Bristol Engine
The 100-series six, BMW-328-derived, that transformed the Aceca.
/bristol-engine
HistoryReferenceGeneral
AC Ace Bristol BE 232, 593 CPC
An ex-works development AC Ace Bristol raced at Goodwood, Shelsley Walsh and Chateau Impney, laid up forty years, and restored by Kevin Kivlochan.
/ace-bristol-be232
HandbookReferenceFuel
Solex 32 BI Carburettors
Guide to the triple Solex 32 BI downdraught carburettors on the Aceca-Bristol.
/solex-carburettors
HandbookFuelIgnition
Tuning the AC Aceca
Balancing triple carbs (SU, Solex, Ruddspeed) and setting Lucas ignition.
/tuning
ReferenceRegistryGeneral
Chassis Numbers & Notable Cars
Decoding AE, BE and RS prefixes; production totals; notable individual cars.
/chassis-guide
RegistryGeneral
Chassis Registry
Public searchable register of surviving AC Aceca chassis.
/registry
RegistryGeneral
Browse the Registry by Variant
Every recorded chassis grouped by Aceca, Aceca-Bristol and Aceca 2.6.
/registry/by-variant
RegistryGeneral
Browse the Registry by Country
Every recorded chassis grouped by the country it is last known in.
/registry/by-country
RegistryGeneral
Registry Map
Where surviving Aceca chassis are located worldwide, by country.
/registry/map
ReferenceGeneral
Gallery
Photographic gallery of AC Aceca and Aceca-Bristol cars.
/gallery
GuideBuyer's GuideGeneral
Buyer's & Ownership Guide
The hub for buying, inspecting and owning an AC Aceca.
/guide
Buyer's GuideGeneral
Buying an AC Aceca
Where to look, how to research a car, and how to complete a considered purchase.
/guide-buying
Buyer's GuideGeneral
Auction, Dealer or Private? Buying an AC Aceca
Pros, cons, costs and legal protection for the three routes to an Aceca, with a pre-purchase checklist and FAQ.
/buying/auction-dealer-or-private
Buyer's GuideGeneral
Buying an AC Aceca: What to Look For
What to check before buying an AC Aceca, the ash frame and electrolytic corrosion, which engine it has, the mechanicals, rarity and provenance.
/buying/what-to-look-for
Buyer's GuideBodyEngine
Pre-purchase Inspection
What to check on an Aceca before you commit to buy.
/guide-inspection
Buyer's GuideGeneral
Authenticity & Provenance
Verifying that a car is what it claims to be.
/guide-authenticity
Buyer's GuideGeneral
Documentation & Paperwork
The history file, V5, service records and other paperwork worth having.
/guide-documentation
Buyer's GuideGeneral
AC Aceca For Sale: What to Pay and How to Verify
What an Aceca costs, where the cars come up, and an eight-step verification checklist before you buy.
/aceca-for-sale-buying-guide
Buyer's GuideReferenceGeneral
AC Aceca Prices & Auction Results
Fifteen sourced AC Aceca and Aceca-Bristol sale results from 2013 to 2026, with price bands by variant.
/values/ac-aceca-prices
Buyer's GuideGeneral
Values & Market
What Acecas are worth and what drives value.
/guide-values
GuideGeneral
Living with an Aceca
Running costs, servicing schedule, insurance, storage.
/guide-ownership
GuideBuyer's GuideEngineCoolingBodyGeneral
Is the AC Aceca a good car, and is it reliable?
An honest answer on AC Aceca reliability: three real design weaknesses, the faults that are down to neglect, and what the repairs actually cost.
/reliability
GuideBuyer's GuideGeneral
AC Aceca Insurance: Agreed Value and Mileage
How to insure an AC Aceca properly, agreed value vs market value, mileage limits, laid-up cover, and what you must declare, with named UK specialist insurers.
/guide-insurance
GuideGeneral
AC Aceca MOT and tax exemption
Every Aceca is over 40 years old: the MOT exemption, the £0 Historic tax class, and the substantial-changes test.
/mot-and-tax-exemption
HandbookGeneral
Handbook hub
The technical handbook: tuning, tyres & wheels, fault-finding, how-to guides.
/handbook
HandbookGeneral
Wheels & Tyres
Original sizes, pressures, modern options, and the classic-tyre age rule.
/handbook/tyres-wheels
HandbookFault FindingEngineCoolingIgnitionFuelElectricalBody
Fault Finding
Symptom → cause → fix reference for the AC Aceca.
/handbook/fault-finding
HandbookGeneral
How-To & Repairs
Task-focused hands-on guides for AC Aceca owners.
/how-to
HandbookGuideGeneral
Before a Long Run, and After: An Aceca Checklist
A pre-trip and post-trip checklist: fluids, tyres, brakes and charging, the Bristol and triple-Solex quirks, spares to carry and the return check.
/how-to/before-a-long-run
HandbookGuideElectrical
The Lucas Control Box: Voltage Regulation on the AC Aceca
What the Lucas RB106 control box does, the symptoms of a misbehaving charging system, and how to cure overcharging.
/how-to/lucas-control-box
HandbookGuideElectrical
Calibrating the Lucas Voltage Regulator on the AC Aceca
Setting the RB106 with a multimeter: the open-circuit method, temperature-corrected voltage targets and the cut-out setting.
/how-to/calibrating-the-lucas-voltage-regulator
HandbookGuideGeneral
Brake Fluid for the AC Aceca: Types, Checking, Choosing and Changing
Glycol DOT 4 and silicone DOT 5 compared, why the Aceca does not use mineral fluid, how to tell which your car runs, checking before a run and when to renew.
/how-to/brake-fluid
HandbookReferenceGeneral
AC Aceca Front Disc Brakes: Calipers, Discs and What Fits
Girling caliper and disc identification for the disc-braked Ace and Aceca: part numbers, the shared TR4/Greyhound caliper, the AC-specific disc, and the caliper-relief fitting detail.
/how-to/front-disc-brakes
HandbookGuideElectrical
Fitting a Solid-State Regulator Inside the Lucas Control Box
Choosing the right positive-earth solid-state unit for the Lucas RB106, fitting it inside the original case, and what to expect on the first run.
/how-to/fitting-a-solid-state-regulator
HandbookGuideGeneralElectrical
AC Aceca Wiring and Looms: Makers, the Lucas Colour Code and Earthing
Replacement Aceca looms are made to order by engine type. The Lucas colour code, where the factory wiring diagrams live, and why a wooden framed car needs so many earth wires.
/how-to/wiring-and-the-loom
ReferenceElectrical
AC Aceca Lucas Wiring Diagrams
The four known Lucas wiring diagram numbers for the AC Ace and Aceca, their dates, what each covers, and how to obtain a copy through the AC Owners Club archives.
/diagrams
HandbookGuideElectrical
Positive Earth: What It Means for Your AC Aceca
Why British cars were positive earth, how to tell whether yours still is, and what it means for the battery, coil, dynamo, charging and modern accessories.
/how-to/positive-earth
HandbookGuideGeneral
AC Aceca Steering & Suspension: The All-Independent Chassis Explained
Transverse-leaf all-independent suspension, tubular wishbones, the ENV final drive and Bishop cam steering, plus the wear points to watch.
/how-to/steering-and-suspension
HandbookGuideGeneral
AC Aceca Brakes: Girling Drums, Al-Fin and the Move to Discs
Girling 11-inch Al-Fin drums, the front discs offered from 1957 and standard from 1958, and how to keep either set-up safe.
/how-to/brakes
HandbookGuideGeneralEngine
The Clutch and Its Hydraulics: Borg & Beck, Two Master Cylinders
Every Aceca has a hydraulically operated Borg & Beck clutch, but the master cylinder differs by engine. The bracket fault to rule out first, and the Bristol freewheel.
/how-to/clutch-and-hydraulics
HandbookGuideGeneralEngine
AC Aceca Gearbox & Freewheel: Moss, Bristol and the Freewheel First Gear
The Moss box on AC-engined cars, the close-ratio Bristol four-speed with its freewheel first gear, the Ruddspeed AC/TR3 box and the overdrive option.
/how-to/gearbox-and-freewheel
HandbookGuideGeneral
Driving a Gearbox with No Synchromesh on First Gear
What synchromesh is, why early boxes lacked it on first, and how to select first cleanly, from rest or on the move, by double-declutching.
/how-to/non-synchromesh-first-gear
HandbookGuideGeneral
AC Aceca Body & Ash Frame: Aluminium, Ash and Where It Rots
Hand-formed aluminium over a steel-tube and ash frame, the fibreglass bulkheads, the early hatchback, and the two ways the body decays.
/how-to/body-and-ash-frame
HandbookGuideBody
How to Prop the Bonnet Open on an AC Aceca
The correct way to prop the Aceca's forward-hinged alloy bonnet so it stays safely open while you work.
/how-to/bonnet-props
HandbookGuideBody
AC Aceca Doors That Won't Shut Tight: Why, and the Fix
Why an AC Aceca's coachbuilt ash-framed doors stop shutting tight, how to read the symptoms, and why the right fix usually starts with hinges before the striker.
/how-to/door-fit-and-adjustment
ReferenceHistoryGeneral
Production Data
Total built and per-variant production figures in machine-readable form.
/production
ReferenceGeneral
Frequently Asked Questions
Categorised FAQ answering every question we can support from research.
/faq
ReferenceGeneral
Press Kit & Citation Resources
Boilerplate copy, fast facts, canonical URLs and citation formats for anyone referencing the archive.
/press-kit
ReferenceGeneral
Aceca vs Aston Martin DB2/4
Comparison feature.
/aceca-vs-db24
ReferenceGeneral
Aceca vs AC Ace
How the coupé Aceca compares with the roadster Ace it was built on.
/aceca-vs-ace
ReferenceGeneral
AC Ace Variants: Ace vs Ace-Bristol vs Ace 2.6
The three AC Ace engines compared: AC Light Six, Bristol 100D2 and the Ford 2.6 Ruddspeed.
/ac-ace-variants
Buyer's GuideGeneral
AC Ace Values: What to Pay
Published AC Ace and Ace-Bristol auction results, price-guide values and what moves the price.
/ac-ace-values
HistoryReferenceGeneral
AC Cars: The Marque, Its History and Its Models
AC Cars of Thames Ditton, from the 1901 Weller and Portwine beginnings through the Ace, Aceca, Greyhound and Cobra to the 428 and 3000ME.
/ac-cars
The CarReferenceEngineGeneral
The AC Ace: The Roadster That Became the Cobra
The AC Ace (1953 to 1963), AC's hand-built Tojeiro-chassis roadster, its AC, Bristol and Ford engines, its racing record, and how it became the AC Cobra.
/ac-ace
HistoryThe CarEngineGeneral
The AC Cobra, and what it shares with the Aceca
The AC Cobra is an AC Ace with a Ford V8. The same Thames Ditton chassis that carries the Aceca beat Ferrari to the 1965 World GT Championship.
/ac-cobra
HistoryThe CarReferenceEngineBodyGeneral
The AC Greyhound, a four-seater grand tourer
The AC Greyhound (1959-1963) was AC Cars' four-seater grand tourer, a longer-wheelbase, coil-sprung sibling of the Aceca-Bristol built at Thames Ditton.
/ac-greyhound
HistoryReferenceGeneral
The 1998 AC Aceca
In 1998 AC revived the Aceca name on a V8 coupe built at Brooklands. It is not the Thames Ditton car, and how it came about repeats 1954 almost exactly.
/aceca-1998
HistoryReferenceGeneral
Cars this archive has documented
Three AC cars followed in detail by this archive: UBR 135, Ace Bristol BE 232 and the Aceca restored on Car SOS. Each page states the evidence it rests on.
/featured
HistoryReferenceEngineGeneral
The AC Aceca on Car SOS
The AC Aceca restored on Car SOS in 2016 was a 1957 car that left Thames Ditton with a Triumph TR3 engine, which is why AC called it a prototype.
/car-sos-aceca
HistoryReferenceGeneral
Famous Owners of the AC Aceca: Donald Campbell & Ian Fleming
Two of the AC Aceca's most famous owners, speed-record legend Donald Campbell and James Bond author Ian Fleming, and the very different Acecas they drove.
/famous-owners
ReferenceGeneral
About the Archive
The archive, sources, and contact.
/about
ReferenceGeneral
Contact, The AC Aceca Archive
Get in touch about the AC Aceca archive, corrections, questions, history and photographs welcome.
/contact
ReferenceGeneral
About the Author
Jon Cosson, owner-enthusiast and independent classic-car researcher.
/about-the-author
HistoryReferenceEngineGeneral
UBR 135, 1958 AC Aceca-Bristol
A matching-numbers 1958 Aceca-Bristol with a documented six-decade history and a Bristol six rebuilt by Stanton Motorsport with Cosworth pistons to around 140 bhp.
/featured/ubr-135
HistoryReferenceEngineGeneral
The Autocar Road Test, 1960, AC Aceca-Bristol
A condensed report of The Autocar's April 1960 road test of the AC Aceca-Bristol, 115 mph, the Bristol 100D2 six, and the car's period quirks.
/archive/autocar-1960-aceca-bristol-road-test
Buyer's GuideThe CarBodyGeneral
The Aceca Body, Aluminium, Steel & Ash
How the Aceca's aluminium body over its steel-and-ash frame is built, how it decays, where to inspect, and what a proper restoration really costs.
/guide-body
GuideReferenceEngineFuel
Fuel, Oil & Additives: Running an Aceca on Modern Pumps
What ethanol, unleaded petrol and low-zinc modern oils do to the AC, Bristol and Ford engines, and which additives actually help.
/fuel-oil-additives
GuideBuyer's GuideBodyGeneral
AC Aceca Interiors: Leather, Upholstery and the Facia
Caring for and restoring an Aceca interior, leather, seats, wool carpet, headlining, the facia and instruments, with a checklist and FAQ.
/guide-interior
HandbookGuideEngineGeneral
Servicing Your AC Aceca-Bristol
A basic home-service guide for the Bristol-engined AC Aceca, intervals, tools, safety, and where each task fits in a full service.
/servicing
HandbookGuideEngine
Changing the Engine Oil & Filter on an AC Aceca-Bristol
The right classic 20W/50, the Vokes vs spin-on filter, and the oil-cooler catch on the Bristol six.
/servicing/engine-oil-and-filter
HandbookGuideEngineIgnition
Spark Plugs on an AC Aceca-Bristol, the 10mm Question
The Bristol engine's small 10mm spark plugs, and how owners run motorcycle plugs as a substitute.
/servicing/spark-plugs
HandbookGuideEngine
Cooling the Bristol Six: Radiator, Water Pump and Running Temperature
Coolant condition, the radiator, water pump and thermostat, hoses, and reading the temperature gauge on the Bristol six.
/servicing/cooling-system
HandbookGuideEngineCooling
Cooling the AC Light Six
An alloy block, an iron head and steel studs make coolant choice a structural question on the AC Light Six. What to use, what to avoid, and the water pump's design flaw.
/servicing/ac-engine-cooling
HandbookGuideEngine
Engine oil and filter on the AC Light Six
Monograde SAE 30 was the factory grade, low hot idle oil pressure is normal, the original filter is not full flow, and why the usual zinc argument does not apply to this engine.
/servicing/ac-engine-oil-and-filter
HandbookGuideEngine
Valve clearances on the AC Light Six
The AC Light Six runs an overhead camshaft on rockers with roller followers. The clearance figure, what the adjustment tells you about wear, and the timing chain.
/servicing/ac-engine-valve-clearances
HandbookGuideEngineElectrical
Spark plugs and ignition on the AC Light Six
Conventional 14mm plugs, not the Bristol's 10mm. Firing order, contact breaker gaps by distributor, and two published ignition timing figures that cannot both be right.
/servicing/ac-engine-spark-plugs-and-ignition
HandbookGuideEngine
Setting the Valve Clearances on the Bristol Cross-Pushrod Head
The Bristol engine's unusual cross-pushrod valve gear, explained, and how to approach setting its valve clearances.
/servicing/valve-clearances
HandbookGuideReferenceEngineCoolingGeneral
Oils & Fluids for the AC Aceca: A Quick Reference
Oils and fluids for the AC Aceca: engine, gearbox, differential, clutch, brakes and cooling, the choices owners rely on, and how the variants differ.
/servicing/oils-and-fluids
HandbookReferenceGeneral
Grease for the Ace and Aceca Suspension and Chassis
Which grease for the Ace and Aceca's suspension and chassis grease points, the obsolete originals, and the modern multipurpose lithium (NLGI 2) equivalent.
/servicing/suspension-grease
HandbookReferenceEngine
Fitting the Oil Temperature Gauge: the Vokes 'Dog's Bone'
Where the oil-temperature sensor goes on a Bristol-engined AC: the 3/8in BSP hole in the Vokes filter's alloy Dog's Bone, the sump fallback, and testing the Smith's capillary gauge.
/how-to/oil-temperature-gauge
HandbookReferenceGeneral
The Steering Box and 'Tracking': Setting Up the Ace and Aceca Steering
The cam-and-peg steering box explained: peg clearance and self-centring, the handbook's 1/16in toe-in per wheel, positive caster, and the real causes of wander.
/how-to/steering-box-and-tracking
HandbookGuideFuel
AC Aceca Fuel System: Tank, Pump and Delivery
The AC Aceca's fuel system: the tank, pump, lines and filter that feed the carburettors, the common faults, and what modern ethanol petrol means for it.
/how-to/fuel-system
HandbookReferenceGeneral
The AC-Engined Car's Gearbox: the Moss Box and the 2-Litre
Early AC-engined Aces and Acecas share the Moss gearbox with the AC 2-litre saloon, but with a hydraulic clutch, a shorter gear lever and a shorter turret for tunnel clearance.
/how-to/ac-engine-gearbox
HandbookGuideFuel
Fuel Pump Location and Over-Fuelling (AC Engine)
Where to mount the fuel pump on an AC-engined Ace or Aceca, and why over-fuelling is usually float height, needle valves or pump pressure, not pump position.
/how-to/fuel-pump-location
HandbookGuideFuel
Setting Solex Float Levels on the Bristol Engine
The Bristol six's triple Solex carburettors have no factory float-level figure. Two proven methods, fuel-level and needle-valve, and the float faults to check when the level is wrong.
/how-to/solex-float-levels
HandbookGuideEngine
Removing the Bristol Camshaft: With the Engine In, or Out?
One owner's account of replacing a Bristol camshaft: the distributor drive gear clip that forces the oil pan off, the timing cover and damper carrier, and his own later correction.
/how-to/bristol-camshaft-removal
HandbookGuideElectrical
Horn and Indicator Wiring: the Stator Tube and Its Lucas Switch
On the Ace and Aceca the horn and indicator wiring runs through the centre of the steering column's stator tube to a delicate Lucas switch. How the wiring routes, the safe way to thread it, and why you must never prise the old switch apart at its base tags.
/how-to/horn-and-indicator-wiring
HandbookGuideFuel
Starting in Extreme Heat: Hot Fuel and the Aceca
Why an AC Aceca is hard to restart on a very hot day: fuel vaporising in the carburettors, the symptoms, the roadside cure and the permanent fixes.
/how-to/starting-in-extreme-heat
HandbookGuideBody
Storing an AC Aceca Over Winter: Damp, Fuel and the Ash Frame
How to lay up an AC Aceca for winter, why its ash frame and alloy body make dry storage essential, plus fuel, battery, brakes and coolant care done right.
/how-to/winter-storage-and-care
HandbookGuideGeneral
Driving an AC Aceca Through the Winter
Using a rare aluminium-and-ash coupe in a British winter: road salt, washing the underside, galvanic corrosion, underbody protection types and when to stay home.
/how-to/winter-driving
HandbookGuideBody
Garage Humidity and Dehumidifiers for an AC Aceca
What humidity to store an aluminium, steel and ash-framed Aceca at, why the sources disagree, desiccant against compressor units, floors, pouches and batteries.
/how-to/storage-humidity-and-dehumidifiers
ReferenceGeneral
Journal
Show reports, auction viewing days and field notes, first-hand, from the road.
/journal
ReferenceGeneral
Mathewsons Live 2026: the Aceca-Bristol at the Great Yorkshire Showground
A day exhibiting UBR 135, our 1958 Aceca-Bristol, at Mathewsons Live: 500-plus classics, a rally stage and a crowd around a rare AC all day.
/journal/mathewsons-live-2026
HandbookFault FindingCooling
Fault: Engine overheats in slow traffic
An Aceca that runs cool on the move but climbs the temperature gauge in traffic is almost always suffering from insufficient airflow through the radiator at low speed, or a tired thermostat/water pump. The cooling system on all three engines is marginal by modern standards and unforgiving of neglect.
/handbook/fault-finding#overheating-in-traffic
HandbookFault FindingFuel
Fault: Idle hunts or will not settle
An unsteady idle on a triple-carburettor Aceca almost always traces to unbalanced airflow between the three carburettors, an air leak past a worn throttle spindle, or a mixture that is drifting. It is a setup problem before it is an engine problem.
/handbook/fault-finding#hunting-idle
HandbookFault FindingIgnition
Fault: Misfire under load or at higher rpm
A misfire that appears when the engine is asked to work, climbing hills, accelerating hard, is far more often ignition than fuel. Points, condenser, HT leads, plugs and distributor cap are the first suspects. All three Aceca engines run a Lucas distributor with points and condenser.
/handbook/fault-finding#misfire-under-load
HandbookFault FindingFuel
Fault: Hard to start when hot
A warm engine that cranks and cranks before catching is usually suffering from fuel percolation in the carburettors or from ignition weakness that a cold engine tolerates. On a triple-carb Aceca the fuel path runs close to hot exhaust manifolding, and modern ethanol-blended fuel makes matters worse.
/handbook/fault-finding#hard-hot-starting
HandbookFault FindingEngine
Fault: Persistent oil leaks
Any 60-year-old British six leaks a little oil; the question is where, and how much. Rear main seals, timing covers, rocker gaskets and sump joints are the usual sources. A dry underside is not the goal, a diagnosed and controlled leak is.
/handbook/fault-finding#oil-leaks-general
HandbookFault FindingGeneral
Fault: Brakes pull to one side
A car that pulls under braking has an imbalance across an axle, usually one wheel cylinder or caliper piston seizing, contamination on one side's linings, or a collapsed flexible hose acting as a one-way valve. Take this seriously and stop driving until diagnosed.
/handbook/fault-finding#brakes-pulling
HandbookFault FindingGeneral
Fault: Gearbox jumps out of gear
A gearbox that pops out of a particular gear on the overrun has worn selector detents, worn synchro hubs, or worn gear teeth. On a 60-year-old box this is a rebuild job, not an adjustment.
/handbook/fault-finding#gearbox-jumps-out
HandbookFault FindingElectrical
Fault: Battery goes flat / ammeter shows no charge
A car of this era runs a dynamo (later cars) and a mechanical voltage regulator, a fundamentally simple charging system with a handful of usual failures. A flat battery after a run is almost always the charging system, not the battery itself.
/handbook/fault-finding#charging-low
HandbookFault FindingBody
Fault: Blistering or white powder on aluminium body panels
White powder or blistering under paint on an Aceca panel is galvanic corrosion, the aluminium body reacting with the steel frame or fasteners through trapped moisture. Left, it eats through the panel. Caught early, it is arrestable.
/handbook/fault-finding#corrosion-alloy-body
HandbookFault FindingGeneral
Fault: Clutch drags, grating engagement, hard to select first
A dragging clutch fails to fully release when the pedal is depressed, so gears grate on engagement. Usual causes are hydraulic (air, low fluid, failing master or slave cylinder) rather than the clutch itself, worth checking before pulling the gearbox.
/handbook/fault-finding#clutch-drag