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Briggs and Stratton 252707 Engine

General Technical Data

Briggs and Stratton 252707 Engine Specifications

Engine Model ............ Briggs and Stratton 252707
Engine Type ............ 4-cycle single cylinder L-head vertical shaft air-cooled gasoline engine
Number of Cylinders ............ 1
Displacement, cu.in (cc) ............ 24.36 (399)
Cylinder Bore, in (mm) ............ 3.44 (87.3)
Piston Stroke, in (mm) ............ 2.63 (66.7)
Rated Engine Power, hp (kW) ............ 11.0 (8.2)
Rated Engine Speed, rpm ............ 3600
Idle Speed, rpm ............ 1750
Maximum Torque, Nm (ft-lbs) ............ 22.7 (16.8)
Torque Speed, rpm ............ 2800
Air Cleaner ............ Dual element, cartridge and pre-cleaner
Cooling System ............ Forced air
Ignition System ............ Transistor module
Starting System ............ Electric starter
Electrical System Rating, Volts ............ 12
Charging System Rating, Amps ............ 3

Fuel System

Fuel System Type ............ Carburetor
Carburetor Type ............ Float
Governor Type ............ Mechanical
Fuel Type ............ Gasoline

Briggs and Stratton 252707 Maintenance Data

Cylinder Block and Valves

Cylinder Bore Inside Diameter (Maximum), in (mm) ............ 3.4375 (87.31)
Cylinder Head (Max. Out of Flatness), in (mm) ............ 0.004 (0.10)
Valve Clearance (Intake), in (mm) ............ 0.003-0.005 (0.08-0.13)
Valve Clearance (Exhaust), in (mm) ............ 0.005-0.007 (0.13-0.18)

Engine Oil and Filters

Engine Oil Type (Summer) ............ SAE 30, 10W-30
Engine Oil Type (Winter) ............ SAE 5W-20, 5W-30
API Service Classifications ............ SE, SF or SG
Oil Capacity, qts (L) ............ 1.5 (1.4)
Fuel Filter Part Number ............ 298090
Air Filter Element Part Number ............ 491519

Carburetor Adjustments

Main Adjustment Screw ............ 1-1/2 turn out
Idle Adjustment Screw ............ 1 turn out
Low Idle Speed, rpm ............ 1650-1800
High Idle Speed, rpm ............ 3300-3600

Ignition System

Spark Plug Type ............ Champion CJ-8 or RJ19LM
Spark Plug Gap, in (mm) ............ 0.03 (0.76)
Armature Air Gap, in (mm) ............ 0.010-0.014 (0.25-0.36)
Spark Plug Torque, Nm (lb-ft) ............ 18 (13.5)

Service Intervals

Service Pre-Cleaner ............ Every 25 hours
Clean Air Filter Cartridge ............ Every 25 hours
Change Engine Oil ............ Every 50 hours
Check and Adjust Spark Plug ............ Every 50 hours
Replace Pre-Cleaner ............ Every 100 hours
Service Air Filter Cartridge ............ Every 100 hours
Change Fuel Filter ............ Every 100 hours
Check Carburetor Adjustment ............ Every 100 hours
Replace Spark Plug ............ Every 100 hours

Briggs and Stratton 252707 Service Specifications

Cylinder Block

Cylinder Bore I.D. (Standard), in (mm) ............ 3.4365 (87.29)
Cylinder Bore I.D. (Maximum), in (mm) ............ 3.4375 (87.31)
Cylinder Bore (Out-Of-Round), in (mm) ............ 0.0015 (0.04)
Main Bearing Bore Diameter (Cylinder Block), in (mm) ............ 1.3795 (35.04)
Main Bearing Bore I.D. (Crankcase Cover), in (mm) ............ 1.3795 (35.03)
Crankshaft Journal O.D. (Magneto Side), in (mm) ............ 1.3775 (35.00)
Crankshaft Journal O.D. (PTO Side), in (mm) ............ 1.3775 (35.00)
Crankshaft End Play, mm (in) ............ 0.002-0.008 (0.05-0.20)
Crank Pin Journal O.D. (Standard), in (mm) ............ 1.2485 (31.72)
Crank Pin Journal O.D. (Wear Limit), in (mm) ............ 1.2470 (31.67)
Camshaft Journal O.D. (Standard), in (mm) ............ 0.499 (12.67)
Camshaft Journal O.D. (Wear Limit), in (mm) ............ 0.498 (12.65)
Cam Lobe (Standard), in (mm) ............ 1.1854 (30.11)
Cam Lobe (Wear Limit), in (mm) ............ 1.1840 (30.07)
Connecting Rod Big End I.D. (Standard), in (mm) ............ 1.2505 (31.76)
Connecting Rod Big End I.D. (Wear Limit), in (mm) ............ 1.2525 (31.81)
Connecting Rod Small End I.D. (Standard), in (mm) ............ 0.8006 (20.33)
Connecting Rod Small End I.D. (Wear Limit), in (mm) ............ 0.801 (20.37)
Piston Pin O.D. (Standard), in (mm) ............ 0.7998 (20.31)
Piston Pin O.D. (Wear Limit), in (mm) ............ 0.799 (20.29)
Piston Pin Bearing I.D. (Standard), in (mm) ............ 0.8006 (20.33)
Piston Pin Bearing I.D. (Wear Limit), in (mm) ............ 0.802 (20.35)
Compression Ring End Gap (Wear Limit), in (mm) ............ 0.035 (0.89)
Oil Ring End Gap (Wear Limit), in (mm) ............ 0.045 (1.14)

Cylinder Head and Valves

Cylinder Head (Max. Out of Flatness), in (mm) ............ 0.004 (0.10)
Valve Clearance (Intake), in (mm) ............ 0.003-0.005 (0.08-0.13)
Valve Clearance (Exhaust), in (mm) ............ 0.005-0.007 (0.13-0.18)
Valve Seat Width, in (mm) ............ 0.047-0.063 (1.19-1.58)
Valve Seat Angle, deg ............ 45
Valve Guide I.D. (Standard), in (mm) ............ 0.311 (7.90)
Valve Guide I.D. (Wear Limit), in (mm) ............ 0.313 (7.94)

Briggs and Stratton 252707 Tightening Torque Specs

Cylinder Head, Lb-ft (Nm) ............ 13.8 (18.6)
Connecting Rod, Lb-ft (Nm) ............ 15.5 (20.9)
Flywheel Nut, Lb-ft (Nm) ............ 65 (87.8)
Crankcase Cover, Lb-ft (Nm) ............ 11.7 (15.8)
Fuel Shut-Off Valve, Lb-ft (Nm) ............ 5.9 (8.0)
Governor Lever Nut, Lb-ft (Nm) ............ 5.2 (7.0)
Spark Plug Torque, Nm (lb-ft) ............ 13.5 (18.0)
Oil Drain Plug, Lb-ft (Nm) ............ 14.9 (20.0)