PXi Engine Series™

PXi Engine Series™

Power and performance.

Our PXi Series™ riding mower engines are made with power and performance, and feature Advanced Debris Management & premium oil and fuel filters for optimal maintenance and upkeep.

  • Full Pressure Lubrication System - This offers a premium oil filter and oil is also being pushed into the crank pin bearing for more durability and longer life.
  • Advanced Debris Managment System - Helps our engines run cleaner and longer by deflecting and ejecting grass and debris, providing a longer life.
  • Chrome-plated exhaust and super finished crankshaft help to reduce friction and minimize wear for additional extended life.
  • Optional: ReadyStart®, Electronic Fuel Management (EFM)

18.0 - 27.0

Gross Torque (ft-lbs)

656 - 810cc

Displacement

Gasoline

Engine Fuel

64 - 67

Oil Capacity (oz)

Features

Made in the USA

Made in the USA of US and global parts.

Qualified 40% Longer Engine Life*

When compared to expected life standards of a Briggs & Stratton Intek™.

Advanced Debris Management System

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

Electronic Fuel Management

Starts as consistently as your car.

Full Pressure Lube System

Reduces component wear for longer engine life.

V-Twin Engine

For more power, comfort and durability.

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

Specs

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Model Number
40S7
Torque (ft-lbs, gross)*
18
Engine Displacement (cc)
656
Number of Cylinders
V-Twin
Engine Configuration
Vertical Shaft
OHV Engine
Yes
Length (in)
19.1
Width (in)
18.2
Height (in)
14.3
Weight (lbs)
84
Bore (in)
2.97
Stroke (in)
2.89
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Full Pressure Lubrication
Oil Capacity (oz)
64
Oil Filter
Premium
Starter
Electric Start
Air Filter
Dual Element Cartridge with Advanced Debris Management
Muffler
N/A
Certified Power Rating
Fuel Shutoff Valve
Optional

*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
40S8
Torque (ft-lbs, gross)*
20
Engine Displacement (cc)
656
Number of Cylinders
V-Twin
Engine Configuration
Vertical Shaft
OHV Engine
Yes
Length (in)
19.1
Width (in)
18.2
Height (in)
14.3
Weight (lbs)
84
Bore (in)
2.97
Stroke (in)
2.89
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Full Pressure Lubrication
Oil Capacity (oz)
64
Oil Filter
Premium
Starter
Electric Start
Air Filter
Dual Element Cartridge with Advanced Debris Management
Muffler
N/A
Certified Power Rating
Fuel Shutoff Valve
Optional

*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
44S6
Torque (ft-lbs, gross)*
22
Engine Displacement (cc)
724
Number of Cylinders
V-Twin
Engine Configuration
Vertical Shaft
OHV Engine
Yes
Length (in)
19.1
Width (in)
18.2
Height (in)
14.3
Weight (lbs)
84
Bore (in)
3.12
Stroke (in)
2.89
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Full Pressure Lubrication
Oil Capacity (oz)
64
Oil Filter
Premium
Starter
Electric Start
Air Filter
Dual Element Cartridge with Advanced Debris Management
Muffler
N/A
Certified Power Rating
Fuel Shutoff Valve
Optional

*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
44S7
Torque (ft-lbs, gross)*
23
Engine Displacement (cc)
724
Number of Cylinders
V-Twin
Engine Configuration
Vertical Shaft
OHV Engine
Yes
Length (in)
19.1
Width (in)
18.2
Height (in)
14.3
Weight (lbs)
84
Bore (in)
3.12
Stroke (in)
2.89
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Full Pressure Lubrication
Oil Capacity (oz)
64
Oil Filter
Premium
Starter
Electric Start
Air Filter
Dual Element Cartridge with Advanced Debris Management
Muffler
N/A
Certified Power Rating
Fuel Shutoff Valve
Optional

*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
44S8
Torque (ft-lbs, gross)*
24
Engine Displacement (cc)
724
Number of Cylinders
V-Twin
Engine Configuration
Vertical Shaft
OHV Engine
Yes
Length (in)
19.1
Width (in)
18.2
Height (in)
14.3
Weight (lbs)
84
Bore (in)
3.12
Stroke (in)
2.89
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Full Pressure Lubrication
Oil Capacity (oz)
64
Oil Filter
Premium
Starter
Electric Start
Air Filter
Dual Element Cartridge with Advanced Debris Management
Muffler
N/A
Certified Power Rating
Fuel Shutoff Valve
Optional

*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
44S9
Torque (ft-lbs, gross)*
25
Engine Displacement (cc)
724
Number of Cylinders
V-Twin
Engine Configuration
Vertical Shaft
OHV Engine
Yes
Length (in)
19.1
Width (in)
18.2
Height (in)
14.3
Weight (lbs)
84
Bore (in)
3.12
Stroke (in)
2.89
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Full Pressure Lubrication
Oil Capacity (oz)
64
Oil Filter
Premium
Starter
Electric Start
Air Filter
Dual Element Cartridge with Advanced Debris Management
Muffler
N/A
Certified Power Rating
Fuel Shutoff Valve
Optional

*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
49S8
Torque (ft-lbs, gross)*
27
Engine Displacement (cc)
810
Number of Cylinders
V-Twin
Engine Configuration
Vertical Shaft
OHV Engine
Yes
Length (in)
19.1
Width (in)
18.7
Height (in)
14.3
Weight (lbs)
87
Bore (in)
3.30
Stroke (in)
2.89
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
N/A
Lubrication System
Full Pressure Lubrication
Oil Capacity (oz)
67
Oil Filter
Premium
Starter
ReadyStart® Starting System, EFM/AutoStart
Air Filter
Dual Element Cartridge with Advanced Debris Management
Muffler
No
Certified Power Rating
Fuel Shutoff Valve
Optional

*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
40S7
40S8
44S6
44S7
44S8
44S9
49S8
Torque (ft-lbs, gross)*
18
20
22
23
24
25
27
Engine Displacement (cc)
656
656
724
724
724
724
810
Number of Cylinders
V-Twin
V-Twin
V-Twin
V-Twin
V-Twin
V-Twin
V-Twin
Engine Configuration
Vertical Shaft
Vertical Shaft
Vertical Shaft
Vertical Shaft
Vertical Shaft
Vertical Shaft
Vertical Shaft
OHV Engine
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Length (in)
19.1
19.1
19.1
19.1
19.1
19.1
19.1
Width (in)
18.2
18.2
18.2
18.2
18.2
18.2
18.7
Height (in)
14.3
14.3
14.3
14.3
14.3
14.3
14.3
Weight (lbs)
84
84
84
84
84
84
87
Bore (in)
2.97
2.97
3.12
3.12
3.12
3.12
3.30
Stroke (in)
2.89
2.89
2.89
2.89
2.89
2.89
2.89
Engine Fuel
Gasoline
Gasoline
Gasoline
Gasoline
Gasoline
Gasoline
Gasoline
Fuel Tank Capacity (gal)
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Lubrication System
Full Pressure Lubrication
Full Pressure Lubrication
Full Pressure Lubrication
Full Pressure Lubrication
Full Pressure Lubrication
Full Pressure Lubrication
Full Pressure Lubrication
Oil Capacity (oz)
64
64
64
64
64
64
67
Oil Filter
Premium
Premium
Premium
Premium
Premium
Premium
Premium
Starter
Electric Start
Electric Start
Electric Start
Electric Start
Electric Start
Electric Start
ReadyStart® Starting System, EFM/AutoStart
Air Filter
Dual Element Cartridge 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
Dual Element Cartridge with Advanced Debris Management
Dual Element Cartridge with Advanced Debris Management
Dual Element Cartridge with Advanced Debris Management
Muffler
N/A
N/A
N/A
N/A
N/A
N/A
No
Fuel Shutoff Valve
Optional
Optional
Optional
Optional
Optional
Optional
Optional

*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.

Support

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