Target Audience:
Triumph Herald owners and mechanics engaged in repair, maintenance, and restoration
Manual Advantage:
Comprehensive coverage for a wide range of years, detailed procedures, diagnostic information, and wiring diagrams, presented in a readily accessible digital format
Feature 1:
Detailed step-by-step instructions with numbered procedures
Feature 2:
Includes notes, cautions, and warnings for critical information
Feature 3:
Extensive use of illustrations, drawings, and photos
Feature 4:
Enlarged insets for detailed part examination
Feature 5:
Combined troubleshooting and electrical service with wiring diagrams
Engine Systems:
Engine overhaul, tuning, lubrication, cooling, fuel delivery (carburettors), ignition system, exhaust system
Transmission Systems:
Gearbox overhaul, clutch, driveshafts
Chassis Systems:
Suspension (front and rear), steering system, braking system (including hydraulic circuits and components), wheels and tires
Electrical Systems:
Wiring diagrams, lighting, starting system, charging system, instrumentation, auxiliary electrics
Body And Trim:
Body repairs, trim components, doors, windows, convertible top (if applicable)
Maintenance:
Routine servicing, lubrication schedules, fluid checks and changes, filter replacements
Diagnostics:
Troubleshooting guides for common and uncommon issues, electrical system diagnostics
Repair:
Step-by-step repair procedures for all major mechanical and electrical components
Rebuild:
Comprehensive procedures for engine, gearbox, and other major component rebuilds
Refurbishment:
Guidance on restoring components and the vehicle to original specifications
Bodywork Repair:
Detailed procedures for panel alignment, rust repair, and structural integrity checks.
Lighting System Repair:
Diagnosis and repair of headlights, taillights, indicators, and interior lighting circuits.
Starting And Charging Systems:
Troubleshooting and repair of the starter motor, dynamo/alternator, and battery circuits.
Interior Trim And Fittings:
Guidance on removing and refitting interior panels, seats, and dashboard components.
Depth:
Professional Technician Level, also suitable for advanced DIY mechanics
Diagnostic Tools Implication:
While advanced electronic diagnostic tools are not relevant, the manual covers traditional diagnostic methods using basic tools and visual inspection.
Engine Type:
Inline 4-cylinder, Overhead Valve (OHV)
Displacement 1200:
1147 cc (70.0 cu in)
Bore 1200:
3.27 in (83 mm)
Stroke 1200:
2.75 in (70 mm)
Compression Ratio 1200:
Approx. 8.0:1
Carburetor 1200:
Single Zenith-Stromberg CD125 or SU H2
Horsepower 1200:
Approx. 38-45 bhp (net) at 4500-4800 rpm (depending on specific tuning and carburation)
Torque 1200:
Approx. 58-62 lb-ft (net) at 2500-3000 rpm
Engine Type 12-50:
Inline 4-cylinder, Overhead Valve (OHV)
Displacement 12-50:
1296 cc (79.1 cu in) (This engine variant is sometimes associated with the later Herald 13/60, but the manual covers models up to 1971 where this could be present or an upgrade. The manual product name specifically lists 1200/12-50, so the 1296cc engine is less likely for the standard 12-50 model but could be a variant in the later years covered by the manual, or a typo in the product description. Assuming the core models are 1147cc for 1200 and potentially a slightly tuned version or early 1296cc for the 12-50 in later years. The manual's broad year range supports covering engine variations.)
Carburetor 12-50:
Often a twin SU H2 or Zenith-Stromberg
Horsepower 12-50:
Approx. 50-55 bhp (net) at 4700-5000 rpm (for the 1296cc variant if applicable to the 12-50 designation)
Fuel Type:
Leaded or Unleaded Petrol (manual will detail conversion/compatibility)
Fuel Pump:
Mechanical, engine-driven
Transmission Type:
4-speed Manual Synchromesh (all forward gears)
Automatic Transmission:
Optional Laycock de Normanville overdrive on top gear (often designated by 'O/D')
Clutch Type:
Single dry plate
Gear Ratios Manual:
Specific ratios will be detailed in the manual, typically around 3.5:1 for 1st, 2.1:1 for 2nd, 1.4:1 for 3rd, 1:1 for 4th
Wheelbase:
Approx. 82 inches (2083 mm)
Length:
Approx. 153 inches (3886 mm)
Width:
Approx. 60 inches (1524 mm)
Height:
Approx. 50 inches (1270 mm) (Saloon)
Kerb Weight:
Approx. 1750-1850 lbs (794-840 kg)
Safety Ratings:
N/A (Contemporary safety standards and testing were significantly different)
Brakes:
Front: Dunlop or Girling Disc Brakes; Rear: Drum Brakes
Steering:
Rack and Pinion Steering
Seatbelts:
Optional (likely lap belts in early models, but later years may have had provision or fitment)
Construction:
Body-on-chassis construction with a distinct 'frame' that also serves as structural support for the body panels
Oil Change Interval:
Typically every 3,000 miles or 6 months, as specified in the manual.
Grease Points:
Regular lubrication of chassis grease points (steering, suspension linkages) is crucial, typically at 3,000-mile intervals.
Ignition Timing:
Regular checks and adjustments are essential for optimal performance and fuel economy.
Engine Oil:
API SF/CD rated multigrade oil, viscosity grade typically 20W-50 or 10W-30 depending on climate. Manual will specify the exact grade and API classification.
Coolant:
Ethylene Glycol based antifreeze mixture (50/50 with water). Manual will specify capacity and type.
Brake Fluid:
DOT 3 or DOT 4 hydraulic fluid. Manual will specify correct type and bleeding procedures.
Gearbox Oil:
GL-4 rated Hypoid gear oil, typically SAE 80W-90. Manual will specify exact type and capacity.
Overdrive Fluid:
If equipped with Laycock overdrive, a specific Type 'A' or Dexron compatible automatic transmission fluid may be required. Manual is essential for this.
Rust Prone Areas:
Wheel arches, sills, floor pans, boot floor, door bottoms, bulkhead are susceptible to corrosion.
Engine Oil Leaks:
Common from crankshaft seals and rocker cover gasket due to age.
Suspension Wear:
Bushings, ball joints, and kingpins require regular inspection and replacement.
Electrical Contact Issues:
Age-related degradation of wiring and connections can lead to intermittent electrical faults.
Carburetor Tuning:
Zenith-Stromberg and SU carburetors require periodic adjustment for smooth running.
Manufacturer:
Standard-Triumph (later part of British Leyland)
Development Context:
Designed by Giovanni Michelotti, the Herald was Triumph's entry into the small-to-medium family car segment, known for its distinctive styling and independent suspension all around.
Variant Progression:
Evolved from the earlier Herald 948cc to the 1200 (1147cc) and the later 13/60 (1296cc). The '12-50' designation specifically refers to the 1200cc model with a hardtop, often featuring a slightly higher trim level or engine tune compared to the standard 1200.
Production Period:
1959 - 1971
Body Styles:
Saloon (2-door and 4-door), Coupe, Convertible, Estate Car (Vitesse derivative often),
