Target Audience:
Luxury car buyers, executives, and those seeking a comfortable, high-performance touring vehicle.
Competitors:
Primarily competed against other high-end European sedans of the era, such as Mercedes-Benz, BMW, and Rolls-Royce (in certain aspects).
Engine Variant:
Powered by Jaguar's renowned 4.2-liter DOHC inline-six engine.
Drivetrain:
Rear-wheel drive
Transmission Options:
Available with a manual gearbox or a Borg-Warner automatic transmission.
Suspension:
Independent suspension front and rear, contributing to its renowned ride quality.
Design:
Elegant styling based on the Jaguar 420, featuring a longer wheelbase and improved rear passenger space, hence the 'G' designation.
Engine:
Detailed coverage including disassembly, assembly, adjustments, and troubleshooting of the XK engine family.
Transmission:
Service procedures for both manual and automatic transmissions used in the 420G S-TYPE.
Fuel System:
Comprehensive details on carburetors (likely SU HD8 or Zenith Stromberg), fuel pumps, lines, and tank.
Cooling System:
Radiator, fan, water pump, thermostat, and coolant passages.
Exhaust System:
Exhaust manifolds, pipes, mufflers, and hangers.
Ignition System:
Distributor, coil, spark plugs, ignition timing, and wiring.
Electrical System:
Wiring diagrams, starter, alternator/generator, battery, lighting, gauges, and ancillary electrical components.
Braking System:
Hydraulic system, master cylinder, brake boosters (likely Girling hydro-vac), calipers, pads, discs, and parking brake.
Suspension System:
Front independent suspension (wishbones, coil springs, telescopic dampers), rear independent suspension (IRS with trailing arms, half shafts, dampers, springs).
Steering System:
Power steering system (likely Burman or Marles), steering column, linkages, and wheel.
Bodywork And Chassis:
Body panel repair, door mechanisms, glass, seals, chassis lubrication points, and structural components.
Interior:
Seating, dashboard, trim panels, heating, ventilation, and climate control components.
Maintenance:
Regular servicing, fluid changes, filter replacements, lubrication, and inspections.
Troubleshooting:
Diagnosis of common problems, symptom-based fault finding, and corrective actions.
Repair:
Step-by-step repair procedures for virtually all mechanical and electrical components.
Disassembly Assembly:
Detailed instructions for removing, dismantling, and reassembling components.
Adjustments:
Precise instructions for setting clearances, timings, pressures, and other critical adjustments.
Installation:
Procedures for installing new or reconditioned parts.
Depth:
Comprehensive, bumper-to-bumper coverage suitable for professional mechanics and experienced DIY enthusiasts.
Diagnostics:
Includes diagnostic procedures, troubleshooting charts, and expected performance values.
Specifications:
Provides essential technical data, service specifications, and allowable limits.
Pictorial Diagrams:
Extensive use of step-by-step explanations, pictorial diagrams, exploded diagrams, drawings, and photos.
Tool References:
References to specific Jaguar service tool numbers and illustrations of tools in use.
Engine Type:
Jaguar XK DOHC Inline-6
Displacement:
4.2 Liters (4235 cc)
Bore X Stroke:
92.07 mm x 106.0 mm (3.625 in x 4.173 in)
Compression Ratio:
8.0:1 or 9.0:1 (depending on market and tune)
Valve Train:
Dual Overhead Camshafts (DOHC), 2 valves per cylinder
Horsepower:
Approximately 245 bhp (183 kW) at 5500 rpm
Torque:
Approximately 283 lb-ft (384 Nm) at 3750 rpm
Carburetion:
Twin SU HD8 or Zenith Stromberg CD carburettors
Fuel Type:
Unleaded gasoline (later models) or Leaded gasoline (early models)
Oil Capacity:
Approximately 7 U.S. quarts (6.6 liters) including filter
Recommended Oil Grade:
Refer to manual for specific viscosities (e.g., SAE 20W50 for warmer climates, SAE 10W/30 for cooler climates)
Standard Transmission Type:
4-speed Manual with Overdrive (Laycock De Normanville Type J)
Optional Transmission Type:
3-speed Borg-Warner Model 8 Automatic Transmission
Overdrive Engagement:
Electrically operated, typically via a switch on the gear lever or dashboard.
Automatic Transmission Fluid:
Refer to manual for specific fluid type (likely Dexron II or equivalent for Borg-Warner).
Manual Transmission Oil:
Refer to manual for specific oil type (e.g., GL-4 gear oil).
Crash Safety:
No official crash test ratings available from modern agencies due to the era of manufacture. Safety features were typical of luxury cars of the mid-to-late 1960s.
Brakes:
Four-wheel Dunlop disc brakes with servo assistance (Girling system).
Steering:
Power-assisted steering for improved maneuverability and control.
Seatbelts:
Provision for seatbelts, often fitted as standard or optional equipment depending on the market and year.
Body Construction:
Robust steel body-on-frame construction typical of the era, providing a significant safety cage.
Safety Equipment:
Safety glass, padded dashboard, collapsible steering column (design dependent on specific year).
Oil Change Interval:
Typically every 3,000-5,000 miles (4,800-8,000 km) or 6 months, as per manual recommendations.
Major Service Interval:
Annual service recommended, with more comprehensive checks at 12,000-18,000 miles (19,000-29,000 km).
Coolant Type:
Ethylene Glycol based antifreeze mixture with water (50/50 recommended).
Brake Fluid Type:
DOT 3 or DOT 4 brake fluid (confirm in manual).
Power Steering Fluid:
Refer to manual for specific type, typically automatic transmission fluid or specialized power steering fluid.
Common Problems:
Rust in common areas (wheel arches, sills, boot floor), potential for oil leaks from engine and gearbox, cooling system overheating if not maintained, wear in suspension bushings and steering components, electrical gremlins due to age.
Recommendations:
Regular lubrication of suspension and steering components, checking and topping up fluids, inspecting braking system, ensuring cooling system is efficient, monitoring for any signs of rust.
Fasteners:
Emphasis on using correct OEM fasteners and torque specifications for reliability and safety.
