Professional Series Single Cylinder
Professional Series Single Cylinder
Professional Series Single Cylinder
Professional Series Single Cylinder
Professional Series Single Cylinder

Professional Series™ (Single Cylinder)

High Performance and Extended Durability

These engines are designed for frequent use in demanding work environments.

15.5 - 19.0

Gross HP

500 - 540cc

Displacement

1

No. of Cylinders

48

Oil Capacity (oz)

Features

Made in the USA

Made in the USA of US and global parts.

Advanced Debris Management System

Keeps the engine clean by deflecting and ejecting grass and debris for a longer engine life.

ReadyStart® for Ride Technology

Automotive-style, no choke easy starting. Just turn the key or push the button and go.

Anti-Vibration System - AVS®

Provides a smoother ride and more comfort.

Full Pressure Lube System

Reduces component wear for longer engine life.

* When compared against the expected life standards of a Briggs & Stratton Intek™ Series Engine.

Specs

Model Number
31S7
Engine Displacement (cc)
500
Engine Configuration
Vertical Shaft
Length (in)
18.9
Height (in)
12.9
Bore (in)
3.56
Engine Fuel
Gasoline
Lubrication System
Full Pressure Lubrication
Oil Filter
Premium
Air Filter
Dual Element Cartridge with Advanced Debris Management
Certified Power Rating
HP (gross) **
15.5
Number of Cylinders
Single
OHV Engine
Yes
Width (in)
16.2
Weight (lbs)
77
Stroke (in)
3.06
Fuel Tank Capacity (gal)
N/A
Oil Capacity (oz)
48
Starter
Electric Start
Muffler
Optional
Marketing Fuel Tank Capacity
N/A
Model Number
31S8
Engine Displacement (cc)
500
Engine Configuration
Vertical Shaft
Length (in)
18.9
Height (in)
12.9
Bore (in)
3.56
Engine Fuel
Gasoline
Lubrication System
Full Pressure Lubrication
Oil Filter
Premium
Air Filter
Dual Element Cartridge with Advanced Debris Management
Certified Power Rating
HP (gross) **
16.5
Number of Cylinders
Single
OHV Engine
Yes
Width (in)
16.2
Weight (lbs)
77
Stroke (in)
3.06
Fuel Tank Capacity (gal)
N/A
Oil Capacity (oz)
48
Starter
Electric Start
Muffler
Optional
Marketing Fuel Tank Capacity
N/A
Model Number
31S9
Engine Displacement (cc)
500
Engine Configuration
Vertical Shaft
Length (in)
18.9
Height (in)
12.9
Bore (in)
3.56
Engine Fuel
Gasoline
Lubrication System
Full Pressure Lubrication
Oil Filter
Premium
Air Filter
Dual Element Cartridge with Advanced Debris Management
Certified Power Rating
HP (gross) **
17.5
Number of Cylinders
Single
OHV Engine
Yes
Width (in)
16.2
Weight (lbs)
77
Stroke (in)
3.06
Fuel Tank Capacity (gal)
N/A
Oil Capacity (oz)
48
Starter
Electric Start
Muffler
Optional
Marketing Fuel Tank Capacity
N/A
Model Number
33S7
Engine Displacement (cc)
540
Engine Configuration
Vertical Shaft
Length (in)
18.9
Height (in)
12.9
Bore (in)
3.7
Engine Fuel
Gasoline
Lubrication System
Full Pressure Lubrication
Oil Filter
Premium
Air Filter
Dual Element Cartridge with Advanced Debris Management
Certified Power Rating
HP (gross) **
18.5
Number of Cylinders
Single
OHV Engine
Yes
Width (in)
16.2
Weight (lbs)
77
Stroke (in)
3.06
Fuel Tank Capacity (gal)
N/A
Oil Capacity (oz)
48
Starter
Electric Start
Muffler
Optional
Marketing Fuel Tank Capacity
N/A
Model Number
33S8
Engine Displacement (cc)
540
Engine Configuration
Vertical Shaft
Length (in)
18.9
Height (in)
12.9
Bore (in)
3.7
Engine Fuel
Gasoline
Lubrication System
Full Pressure Lubrication
Oil Filter
Premium
Air Filter
Dual Element Cartridge with Advanced Debris Management
Certified Power Rating
HP (gross) **
19
Number of Cylinders
Single
OHV Engine
Yes
Width (in)
16.2
Weight (lbs)
77
Stroke (in)
3.06
Fuel Tank Capacity (gal)
N/A
Oil Capacity (oz)
48
Starter
Electric Start
Muffler
Optional
Marketing Fuel Tank Capacity
N/A

*All power levels are stated gross torque at 2600 rpm per SAE J1940 as rated by Briggs & Stratton.
**All power levels are stated gross horsepower at 3600 rpm per SAE J1940 as rated by Briggs & Stratton.

Model Number
31S7
31S8
HP (gross) **
15.5
16.5
Engine Displacement (cc)
500
500
Number of Cylinders
Single
Single
Engine Configuration
Vertical Shaft
Vertical Shaft
OHV Engine
Yes
Yes
Length (in)
18.9
18.9
Width (in)
16.2
16.2
Height (in)
12.9
12.9
Weight (lbs)
77
77
Bore (in)
3.56
3.56
Stroke (in)
3.06
3.06
Engine Fuel
Gasoline
Gasoline
Fuel Tank Capacity (gal)
N/A
N/A
Lubrication System
Full Pressure Lubrication
Full Pressure Lubrication
Oil Capacity (oz)
48
48
Oil Filter
Premium
Premium
Starter
Electric Start
Electric Start
Air Filter
Dual Element Cartridge with Advanced Debris Management
Dual Element Cartridge with Advanced Debris Management
Muffler
Optional
Optional
Marketing Fuel Tank Capacity
N/A
N/A

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