Suzuki F8A Specifications
| Engine Model: Suzuki F8A |
| Engine Type: 4-cycle inline 4-cylinder SOHC 8-valve liquid-cooled gasoline |
| Total Displacement: 48.6 cu.in (0.79 L) |
| Rated Engine Power: 40 Hp (30 kW) at 5500 rpm |
| Fuel System Type: Carburetor |
____________________________________________________________________________________
The Suzuki F8A is a 0.8-liter, inline-four, naturally
aspirated gasoline engine that holds a foundational position in Suzuki’s
automotive history. Introduced in the late 1970s, the F8A represented Suzuki’s
first four-cylinder four-stroke engine, marking a significant departure from the
two-stroke engines that had powered the company’s earlier kei cars and
commercial vehicles. This engine established the architectural template for the
legendary F-family of powerplants, which would later expand to include 1.0-liter
and 1.3-liter variants that powered millions of Suzuki vehicles worldwide.
The F8A is characterized by its cast iron cylinder block and aluminum cylinder
head, a single overhead camshaft (SOHC) valvetrain with eight valves, and a
carbureted fuel system. Its compact dimensions and simple mechanical design
prioritized durability, ease of maintenance, and fuel efficiency - qualities
that made it suitable for light commercial vehicles, kei cars, and export
markets where reliability in basic transportation was paramount. The F8A served
as the powerplant for early Suzuki Carry light trucks, the SJ410 Jimny, and
various kei car models, establishing a reputation for robust construction that
would carry forward through the F-series engine lineage.
The F8A is a four-stroke, water-cooled, naturally aspirated inline-four gasoline
engine configured for longitudinal mounting in rear-wheel-drive and
four-wheel-drive vehicle architectures, as well as transverse mounting in
front-wheel-drive applications. Its small displacement and compact packaging
were optimized for light commercial and kei-class vehicles.
Engine Type: Inline-4, 4-cycle, water-cooled, naturally aspirated
Displacement: 797 cc (48.6 cu.in)
Bore and Stroke: 62.0 mm (2.44 in) x 66.0 mm (2.60 in)
Compression Ratio: 8.7:1
Valvetrain: SOHC, 8-valve (2 valves per cylinder) with belt drive
Fuel System: Carburetor (single downdraft or side-draft depending on
application)
Firing Order: 1-3-4-2
Redline: 6,000 rpm
Maximum Power: 30 kW (40 hp) at 5,500 rpm
Maximum Torque: 60 Nm (44 lb-ft) at 3,500 rpm
The cylinder block is manufactured from gray cast iron,
a material selected for its exceptional durability, wear resistance, and
vibration-damping properties. The block features a closed-deck design, with the
cylinder bores fully enclosed by the water jacket structure at the top deck
surface, providing maximum cylinder head gasket clamping force. Cast-in-place
cylinder bores are machined directly into the iron casting, with a finished
surface honed to precise tolerances.
The block incorporates a deep-skirt design extending below the crankshaft
centerline, providing robust support for the main bearing caps. The main bearing
caps are cast iron with a two-bolt configuration. The block is configured for
multiple mounting orientations - longitudinal for rear-wheel-drive and
four-wheel-drive applications, and transverse for front-wheel-drive variants -
with provisions for different engine mount brackets. A stamped steel oil pan is
sealed to the lower crankcase, providing a large oil reservoir while
contributing to overall engine mass reduction.
Block Material: Cast iron
Bore Diameter: 62.0 mm (2.44 in)
Main Bearing Caps: Cast iron, two-bolt design
The cylinder head is manufactured from aluminum alloy
to reduce overall engine mass and improve heat dissipation from the combustion
chambers. The head utilizes a cross-flow design with the intake manifold on one
side and the exhaust manifold on the opposite side, optimized for the specific
vehicle configuration. The SOHC valvetrain operates eight valves - two per
cylinder - via rocker arms with adjustment screws for manual valve clearance
setting.
The camshaft is driven by a reinforced rubber timing belt from the crankshaft,
with an automatic spring-loaded tensioner maintaining belt tension. The engine
is of interference design; timing belt failure results in valve-to-piston
contact. The combustion chambers are of a wedge design, a configuration that
promotes efficient flame propagation and allows for straightforward valvetrain
layout. The valves are seated on hardened steel inserts pressed into the
cylinder head.
Head Material: Aluminum alloy
Valve Configuration: SOHC, 2 valves per cylinder with rocker arms
Valve Diameter (Intake): 32.0 mm (1.26 in)
Valve Diameter (Exhaust): 28.0 mm (1.10 in)
Valve Stem Diameter: 7.0 mm (0.28 in)
Valve Seat Angle: 45 degrees
Valve Clearance (Cold, Intake): 0.15-0.20 mm (0.006-0.008 in)
Valve Clearance (Cold, Exhaust): 0.20-0.25 mm (0.008-0.010 in)
The F8A employs a carbureted fuel system, reflecting
the engine’s design era. A single carburetor - either a downdraft or side-draft
type depending on the vehicle application - is mounted on the intake manifold.
The carburetor incorporates an automatic choke system on most variants, with a
manual choke available on certain export or basic-specification models.
The carburetor includes a float chamber, main metering system, idle system,
accelerator pump, and power valve to provide appropriate air-fuel mixtures
across all operating conditions. A mechanical fuel pump, driven by the camshaft,
draws fuel from the tank and delivers it to the carburetor. A fuel filter is
mounted in the fuel supply line to remove contaminants. The intake manifold is a
cast aluminum or cast iron design depending on the application, with provisions
for the carburetor mounting flange.
Fuel System: Single carburetor (downdraft or side-draft)
Carburetor Type: Aisan or Mikuni depending on application
Choke System: Automatic or manual depending on variant
Fuel Pump: Mechanical, camshaft-driven
Fuel Requirement: 87 octane or higher
The lubrication system is a fully pressurized, wet-sump
design utilizing a gear-type oil pump mounted to the front of the crankshaft.
The oil pump draws lubricant from a stamped steel oil pan through a mesh
strainer and circulates it through a full-flow, replaceable oil filter before
entering the main oil gallery. From the gallery, pressurized oil is distributed
to the crankshaft main bearings, connecting rod bearings, camshaft bearings, and
rocker arm assemblies.
A pressure relief valve integrated into the oil pump maintains system pressure
within operational limits to prevent over-pressurization during cold starts or
high engine speeds. The oil pan incorporates a baffle to maintain oil pickup
during cornering and acceleration. The system is designed to provide adequate
lubrication across the engine’s operating temperature range with the specified
oil viscosity.
Oil Type: SAE 10W-30, 10W-40, or 20W-50 (API SF, SG, or higher)
Oil Capacity (with filter): 2.8-3.2 liters (3.0-3.4 US qt)
Oil Pressure (at 3,000 rpm): 294-392 kPa (42.6-56.9 psi)
Oil Pressure (at idle): 98 kPa (14.2 psi) minimum
Oil Pump Type: Gear-type, crankshaft-driven
The cooling system is a pressurized, liquid-cooled
design employing a cross-flow copper or aluminum radiator with a mechanical fan
on commercial vehicle applications and an electric fan on passenger car
variants. A centrifugal-type water pump, driven by the timing belt, circulates
coolant through the cylinder block, cylinder head, and heater core.
A wax-pellet thermostat regulates coolant flow to maintain optimal operating
temperature, with a bypass circuit that allows the engine to warm rapidly. The
system is designed to provide uniform cooling across all four cylinders,
maintaining consistent thermal expansion across the cast iron block and aluminum
head interface. A coolant recovery tank is integrated on later applications to
maintain system pressure and prevent coolant loss.
Coolant Type: Ethylene-glycol based antifreeze with corrosion inhibitors
Coolant Capacity: 4.0-4.5 liters (4.2-4.8 US qt)
Thermostat Opening Temperature: 82-86 °C (180-187 °F)
Thermostat Full-Open Temperature: 95 °C (203 °F)
Radiator Cap Pressure: 88-108 kPa (12.8-15.7 psi)
Water Pump Type: Centrifugal, timing belt-driven
Ignition System: Distributor-based ignition system with
a crankshaft-driven distributor on earlier variants and a camshaft-driven
distributor on later variants. The distributor houses the ignition points on
early versions, with later versions utilizing a breakerless electronic ignition
system. A mechanical advance mechanism adjusts ignition timing based on engine
speed.
Intake System: Air is drawn through a dry-type paper element air filter before
entering the carburetor. The intake manifold is a cast design with a plenum
chamber sized for the engine’s displacement.
Exhaust System: Cast iron exhaust manifold with individual runners collecting
into a single downpipe.
Timing Drive: A reinforced rubber timing belt with integral teeth drives the
camshaft from the crankshaft sprocket. An automatic spring-loaded tensioner
maintains belt tension. The engine is of interference design; timing belt
failure results in valve-to-piston contact.
Overall Length: 530 mm (20.9 in)
Overall Width: 570 mm (22.4 in)
Overall Height: 620 mm (24.4 in)
Dry Weight (complete engine): 85 kg (187 lb)
Oil Change Interval: 5,000 km (3,000 mi) under normal
driving conditions.
Oil Filter Change: At every oil change.
Timing Belt Replacement: 60,000 km (37,000 mi) or 4 years.
Engine Coolant Replacement: 40,000 km (25,000 mi) or 2 years.
Spark Plug Replacement: 15,000 km (9,000 mi) for standard plugs.
Spark Plug Type: NGK BP5ES or equivalent.
Spark Plug Gap: 0.7-0.8 mm (0.028-0.031 in).
Drive Belt (Accessory) Inspection: Every 5,000 km (3,000 mi) for tension,
cracking, and glazing.
Air Filter Replacement: 20,000 km (12,000 mi) or as indicated by inspection.
Fuel Filter Replacement: 20,000 km (12,000 mi) for external filter types.
Valve Clearance Adjustment: Inspect and adjust every 15,000 km (9,000 mi).
Intake Valve Clearance: 0.15-0.20 mm (0.006-0.008 in) cold.
Exhaust Valve Clearance: 0.20-0.25 mm (0.008-0.010 in) cold.
Ignition Timing: 8-10 degrees before top dead center at idle.
Idle Speed Adjustment: 800-850 rpm with no electrical or accessory load.
Cylinder Head Bolts (M10 x 1.25), 1st pass: 20 Nm (15
lb-ft).
Cylinder Head Bolts (M10 x 1.25), 2nd pass: 45 Nm (33 lb-ft).
Cylinder Head Bolts (M10 x 1.25), final pass: 60 Nm (44 lb-ft).
Main Bearing Cap Bolts (M10 x 1.25): 40-45 Nm (30-33 lb-ft).
Connecting Rod Cap Bolts (M8 x 1.0): 20-25 Nm (15-18 lb-ft).
Camshaft Bearing Cap Bolts (M8 x 1.25): 18-22 Nm (13-16 lb-ft).
Rocker Arm Shaft Bolts (M8 x 1.25): 18-22 Nm (13-16 lb-ft).
Intake Manifold Bolts (M8 x 1.25): 16-20 Nm (12-15 lb-ft).
Exhaust Manifold Nuts (M8 x 1.25): 16-20 Nm (12-15 lb-ft).
Spark Plugs: 18-22 Nm (13-16 lb-ft).
Oil Pan Bolts (M6 x 1.0): 8-10 Nm (71-89 lb-in).
Water Pump Bolts (M8 x 1.25): 18-22 Nm (13-16 lb-ft).
Timing Belt Tensioner Bolt (M8 x 1.25): 18-22 Nm (13-16 lb-ft).
Crankshaft Pulley Bolt (M12 x 1.25): 70-80 Nm (52-59 lb-ft).
Flywheel / Drive Plate Bolts (M10 x 1.25): 55-60 Nm (41-44 lb-ft).
The Suzuki F8A engine was utilized across Suzuki’s
light commercial vehicle, kei car, and compact off-road vehicle range throughout
the late 1970s and 1980s, serving as the foundation for the F-engine family.
Suzuki Carry / Super Carry (ST80, ST90, SK408): Late 1970s-1980s model years
(0.8-liter variants).
Suzuki Jimny (SJ410): 1979-1985 model years (export market variants with F8A).
Suzuki Cervo (SS20): 1977-1982 model years (0.8-liter variants).
Suzuki Alto (SS30, SS40): 1979-1984 model years (export market variants with
F8A).
Suzuki Every: Early van and pickup variants with 0.8-liter engine.
____________________________________________________________________________________
| Car Engines Technical Specifications |
| Small Engines Technical Specifications |
| Industrial Engines Technical Specifications |
| Outboard Engines Technical Specifications |
