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        EX Series™ Engines

        EX Series Engines
        EX Series Engines
        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. Superior air filtering and reduced vibration come standard. Make starting easier – just like a car – with our optional no choke technology.

        344 - 540cc

        Displacement

        Gas

        Engine Fuel
        Feature

        Features

        Made in the USA

        Made in the USA of US and global parts.

        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.

        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
        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)
        Oil Capacity (oz)
        48
        Lubrication System
        Partial Lubrication System
        Oil Filter
        Standard
        Starter
        Electric Start, Recoil Optional
        Air Filter
        Cartridge Air Cleaner with Advanced Debris Management
        Muffler
        Optional
        Fuel Shutoff Valve
        Optional
        Certified Power Rating
        Download Power Curve
        Marketing Oil Capacity
        48
        Marketing Number of Cylinders
        1
        Marketing Gross Horsepower
        10.5 - 19.0
        Gross Horsepower
        10.5

        *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
        21R8
        Torque (ft-lbs, gross)*
        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)
        Oil Capacity (oz)
        48
        Lubrication System
        Partial Lubrication System
        Oil Filter
        Standard
        Starter
        Electric Start, Recoil Optional
        Air Filter
        Cartridge Air Cleaner with Advanced Debris Management
        Muffler
        Optional
        Fuel Shutoff Valve
        Optional
        Certified Power Rating
        Download Power Curve
        Marketing Oil Capacity
        48
        Marketing Number of Cylinders
        1
        Marketing Gross Horsepower
        10.5 - 19.0
        Gross Horsepower
        11.5

        *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
        31R5
        Torque (ft-lbs, gross)*
        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
        Oil Capacity (oz)
        48
        Lubrication System
        Partial Lubrication System
        Oil Filter
        Standard
        Starter
        Electric Start
        Air Filter
        Cartridge Air Cleaner with Advanced Debris Management
        Muffler
        Optional
        Fuel Shutoff Valve
        Optional
        Certified Power Rating
        Download Power Curve
        Marketing Oil Capacity
        48
        Marketing Number of Cylinders
        1
        Marketing Gross Horsepower
        10.5 - 19.0
        Gross Horsepower
        13.5

        *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
        31R6
        Torque (ft-lbs, gross)*
        14.5
        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
        Oil Capacity (oz)
        48
        Lubrication System
        Partial Lubrication System
        Oil Filter
        Standard
        Starter
        Electric Start
        Air Filter
        Cartridge Air Cleaner with Advanced Debris Management
        Muffler
        Optional
        Fuel Shutoff Valve
        Optional
        Certified Power Rating
        Download Power Curve
        Marketing Oil Capacity
        48
        Marketing Number of Cylinders
        1
        Marketing Gross Horsepower
        10.5 - 19.0
        Gross Horsepower
        14.5

        *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
        31R7
        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
        Oil Capacity (oz)
        48
        Lubrication System
        Partial Lubrication System
        Oil Filter
        Premium
        Starter
        Electric Start
        Air Filter
        Dual Element Cartridge with Advanced Debris Management
        Muffler
        Optional
        Fuel Shutoff Valve
        Optional
        Certified Power Rating
        Download Power Curve
        Marketing Oil Capacity
        48
        Marketing Number of Cylinders
        1
        Marketing Gross Horsepower
        10.5 - 19.0
        Gross Horsepower
        15.5

        *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
        31R8
        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
        Oil Capacity (oz)
        48
        Lubrication System
        Partial Lubrication System
        Oil Filter
        Premium
        Starter
        Electric Start
        Air Filter
        Dual Element Cartridge with Advanced Debris Management
        Muffler
        Optional
        Fuel Shutoff Valve
        Optional
        Certified Power Rating
        Download Power Curve
        Marketing Oil Capacity
        48
        Marketing Number of Cylinders
        1
        Marketing Gross Horsepower
        10.5 - 19.0
        Gross Horsepower
        16.5

        *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
        31R9
        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
        Oil Capacity (oz)
        48
        Lubrication System
        Partial Lubrication System
        Oil Filter
        Premium
        Starter
        Electric Start
        Air Filter
        Dual Element Cartridge with Advanced Debris Management
        Muffler
        Optional
        Fuel Shutoff Valve
        Optional
        Certified Power Rating
        Download Power Curve
        Marketing Oil Capacity
        48
        Marketing Number of Cylinders
        1
        Marketing Gross Horsepower
        10.5 - 19.0
        Gross Horsepower
        17.5

        *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
        33R7
        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
        Oil Capacity (oz)
        48
        Lubrication System
        Partial Lubrication System
        Oil Filter
        Standard
        Starter
        Electric Start
        Air Filter
        Cartridge Air Cleaner with Advanced Debris Management
        Muffler
        Optional
        Fuel Shutoff Valve
        Optional
        Certified Power Rating
        Download Power Curve
        Marketing Oil Capacity
        48
        Marketing Number of Cylinders
        1
        Marketing Gross Horsepower
        10.5 - 19.0
        Gross Horsepower
        18.5

        *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
        33R8
        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
        Oil Capacity (oz)
        48
        Lubrication System
        Full Pressure Lubrication
        Oil Filter
        Premium
        Starter
        Electric Start
        Air Filter
        Dual Element Cartridge with Advanced Debris Management
        Muffler
        Optional
        Fuel Shutoff Valve
        Optional
        Certified Power Rating
        Download Power Curve
        Marketing Oil Capacity
        48
        Marketing Number of Cylinders
        1
        Marketing Gross Horsepower
        10.5 - 19.0
        Gross Horsepower
        19

        *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
        21R7
        21R8
        31R5
        31R6
        31R7
        31R8
        31R9
        33R7
        33R8
        Engine Displacement (cc)
        344
        344
        500
        500
        500
        500
        500
        540
        540
        Number of Cylinders
        Single
        Single
        Single
        Single
        Single
        Single
        Single
        Single
        Single
        Engine Configuration
        Vertical Shaft
        Vertical Shaft
        Vertical Shaft
        Vertical Shaft
        Vertical Shaft
        Vertical Shaft
        Vertical Shaft
        Vertical Shaft
        Vertical Shaft
        OHV Engine
        true
        true
        true
        true
        true
        true
        true
        true
        true
        Length (in)
        17.8
        17.8
        18.9
        18.9
        18.9
        18.9
        18.9
        18.9
        18.9
        Width (in)
        15.5
        15.5
        15.5
        15.5
        15.5
        15.5
        15.5
        16.2
        16.2
        Height (in)
        12.9
        12.9
        12.9
        12.9
        12.9
        12.9
        12.9
        12.9
        12.9
        Weight (lbs)
        66
        66
        77
        77
        77
        77
        77
        77
        77
        Bore (in)
        3.44
        3.44
        3.56
        3.56
        3.56
        3.56
        3.56
        3.70
        3.70
        Stroke (in)
        2.26
        2.26
        3.06
        3.06
        3.06
        3.06
        3.06
        3.06
        3.06
        Engine Fuel
        Gasoline
        Gasoline
        Gasoline
        Gasoline
        Gasoline
        Gasoline
        Gasoline
        Gasoline
        Gasoline
        Fuel Tank Capacity (gal)
        0.7 (optional)
        0.7 (optional)
        N/A
        N/A
        N/A
        N/A
        N/A
        N/A
        N/A
        Oil Capacity (oz)
        48
        48
        48
        48
        48
        48
        48
        48
        48
        Lubrication System
        Partial Lubrication System
        Partial Lubrication System
        Partial Lubrication System
        Partial Lubrication System
        Partial Lubrication System
        Partial Lubrication System
        Partial Lubrication System
        Partial Lubrication System
        Full Pressure Lubrication
        Oil Filter
        Standard
        Standard
        Standard
        Standard
        Premium
        Premium
        Premium
        Standard
        Premium
        Starter
        Electric Start, Recoil Optional
        Electric Start, Recoil Optional
        Electric Start
        Electric Start
        Electric Start
        Electric Start
        Electric Start
        Electric Start
        Electric Start
        Air Filter
        Cartridge Air Cleaner with Advanced Debris Management
        Cartridge Air Cleaner with Advanced Debris Management
        Cartridge Air Cleaner with Advanced Debris Management
        Cartridge Air Cleaner with Advanced Debris Management
        Dual Element Cartridge with Advanced Debris Management
        Dual Element Cartridge with Advanced Debris Management
        Dual Element Cartridge with Advanced Debris Management
        Cartridge Air Cleaner with Advanced Debris Management
        Dual Element Cartridge with Advanced Debris Management
        Muffler
        Optional
        Optional
        Optional
        Optional
        Optional
        Optional
        Optional
        Optional
        Optional
        Fuel Shutoff Valve
        Optional
        Optional
        Optional
        Optional
        Optional
        Optional
        Optional
        Optional
        Optional
        Certified Power Rating
        Download Power Curve
        Download Power Curve
        Download Power Curve
        Download Power Curve
        Download Power Curve
        Download Power Curve
        Download Power Curve
        Download Power Curve
        Download Power Curve
        Marketing Oil Capacity
        48
        48
        48
        48
        48
        48
        48
        48
        48
        Marketing Number of Cylinders
        1
        1
        1
        1
        1
        1
        1
        1
        1
        Marketing Gross Horsepower
        10.5 - 19.0
        10.5 - 19.0
        10.5 - 19.0
        10.5 - 19.0
        10.5 - 19.0
        10.5 - 19.0
        10.5 - 19.0
        10.5 - 19.0
        10.5 - 19.0
        Gross Horsepower
        10.5
        11.5
        13.5
        14.5
        15.5
        16.5
        17.5
        18.5
        19
        Torque (ft-lbs, gross)*
        11.5
        13.5
        14.5

        *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.

        Push Mower Engines

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