EX Series Engines

EX Series Engines

Efficient and durable performance.

With more power and features, our EX Series riding mower engines give you the performance you need. The lubrication system extends engine life, and includes a standard oil filter and oil pump to push clean oil to critical components.

10.5 - 19.0

Gross Horsepower (HP)

344 - 540cc

Displacement

Gas

Engine Fuel

48

Oil Capacity (oz)

Features

Made in the USA

Made in the USA of US and global parts.

AVS® Anti-Vibration System

Provides a smoother ride and more comfort.

Advanced Debris Management System

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

Full Pressure Lube System

Reduces component wear for longer engine life.

Specs

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Model Number
21R7
Gross Horsepower (ft-lbs)*
10.5
Engine Displacement (cc)
344
Number of Cylinders
Single
Engine Configuration
Vertical Shaft
OHV Engine
true
Length (in)
17.8
Width (in)
15.5
Height (in)
12.9
Weight (lbs)
66
Bore (in)
3.44
Stroke (in)
2.26
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
0.7 (optional)
Lubrication System
Partial Lubrication System
Oil Capacity (oz)
48
Oil Filter
Standard
Starter
Electric Start, Recoil Optional
Air Filter
Cartridge Air Cleaner with Advanced Debris Management
Muffler
Optional
Certified Power Rating
Fuel Shutoff Valve
Optional

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

Model Number
21R8
Gross Horsepower (ft-lbs)*
11.5
Engine Displacement (cc)
344
Number of Cylinders
Single
Engine Configuration
Vertical Shaft
OHV Engine
true
Length (in)
17.8
Width (in)
15.5
Height (in)
12.9
Weight (lbs)
66
Bore (in)
3.44
Stroke (in)
2.26
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
0.7 (optional)
Lubrication System
Partial Lubrication System
Oil Capacity (oz)
48
Oil Filter
Standard
Starter
Electric Start, Recoil Optional
Air Filter
Cartridge Air Cleaner with Advanced Debris Management
Muffler
Optional
Certified Power Rating
Fuel Shutoff Valve
Optional

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

Model Number
31R5
Gross Horsepower (ft-lbs)*
13.5
Engine Displacement (cc)
500
Number of Cylinders
Single
Engine Configuration
Vertical Shaft
OHV Engine
true
Length (in)
18.9
Width (in)
15.5
Height (in)
12.9
Weight (lbs)
77
Bore (in)
3.56
Stroke (in)
3.06
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Partial Lubrication System
Oil Capacity (oz)
48
Oil Filter
Standard
Starter
Electric Start
Air Filter
Cartridge Air Cleaner with Advanced Debris Management
Muffler
Optional
Certified Power Rating
Fuel Shutoff Valve
Optional

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

Model Number
31R7
Gross Horsepower (ft-lbs)*
15.5
Engine Displacement (cc)
500
Number of Cylinders
Single
Engine Configuration
Vertical Shaft
OHV Engine
true
Length (in)
18.9
Width (in)
15.5
Height (in)
12.9
Weight (lbs)
77
Bore (in)
3.56
Stroke (in)
3.06
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Partial Lubrication System
Oil Capacity (oz)
48
Oil Filter
Standard
Starter
Electric Start
Air Filter
Cartridge with Advanced Debris Management
Muffler
Optional
Certified Power Rating
Fuel Shutoff Valve
Optional

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

Model Number
31R9
Gross Horsepower (ft-lbs)*
17.5
Engine Displacement (cc)
500
Number of Cylinders
Single
Engine Configuration
Vertical Shaft
OHV Engine
true
Length (in)
18.9
Width (in)
15.5
Height (in)
12.9
Weight (lbs)
77
Bore (in)
3.56
Stroke (in)
3.06
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Partial Lubrication System
Oil Capacity (oz)
48
Oil Filter
Standard
Starter
Electric Start
Air Filter
Cartridge with Advanced Debris Management
Muffler
Optional
Certified Power Rating
Fuel Shutoff Valve
Optional

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

Model Number
33R8
Gross Horsepower (ft-lbs)*
19
Engine Displacement (cc)
540
Number of Cylinders
Single
Engine Configuration
Vertical Shaft
OHV Engine
true
Length (in)
18.9
Width (in)
16.2
Height (in)
12.9
Weight (lbs)
77
Bore (in)
3.70
Stroke (in)
3.06
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Full Pressure Lubrication
Oil Capacity (oz)
48
Oil Filter
Standard
Starter
Electric Start
Air Filter
Dual Element Cartridge with Advanced Debris Management
Muffler
Optional
Certified Power Rating
Fuel Shutoff Valve
Optional

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

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