The Briggs and Stratton 386447 Vanguard is a 627 cc (38.2 cu·in) V-twin air-cooled four-stroke internal combustion gasoline engine, manufactured by Briggs and Stratton.
The B&S 386447 engine has an OHV (overhead valve) design and a horizontal PTO shaft. This engine is equipped with float type, side-draft carburetor and an electronic ignition system. The B&S 386447 engine used Dual-Clean air cleaner (paper element with a foam pre-cleaner).
The cylinder bore is 75.5 mm (2.97 in) and the piston stroke is 70.0 mm (2.75 in). This engine produced 23.3 PS (17.1 KW; 22.9 HP) at 3,600 rpm of horsepower.
The breakdown of the engine code is as follows:
- 38 – Displacement
- 6 – Basic design series
- 4 – Horizontal PTO-shaft
- 4 – Ball bearing, flange mounting, pressure lubrication
- 7 – Electric starter
General information
Engine Specifications | |
Model | B&S 386447 Vanguard |
Type | 4-stroke, OHV, V-twin |
Displacement | 627 cm 3 (38.2 cu-in) |
Max. horsepower | 23.3 PS (17.1 KW; 23.0 HP) at 3,600 rpm |
Max. torque | – |
Fuel system | Float type, side-draft carburetor |
Cooling system | Forced-air |
Ignition system | Electronic |
Lubricating system | Pressure lubrication, oil cooler |
Starting system | Electric starter |
Fuel used | Gasoline |
Fuel tank capacity | – |
Cylinder Block and Head
Cylinder block | ||
Bore x Stroke | 75.5 mm X 70.0 mm (2.97 x 2.76 in) | |
Sleeve internal diameter | 75.500-75.520 mm (2.9724-2.9730 in) | |
Number of piston rings (compression / oil): | 2 / 1 | |
Side clearance | Top | 0.045-0.076 mm (0.0018-0.003 in) |
Second | 0.045-0.076 mm (0.0018-0.003 in) | |
Oil | 0.110-0.150 mm (0.0043-0.0059 in) | |
Ring end gap | Top | 0.200-0.400 mm (0.0079-0.0157 in) |
Second | 0.200-0.400 mm (0.0079-0.0157 in) | |
Oil | 0.200-0.400 mm (0.0079-0.0157 in) | |
Connecting rod small end ID | 18.040-18.050 mm (0.7100-0.7105 in) | |
Piston pin outer diameter | 18.000-18.010 mm (0.7085-0.7090 in) | |
Cylinder Head | ||
Valve Arrangement: | OHV | |
Valves: | 4 (2 per cylinder) | |
Valve steam diameter | INTAKE | 5.950-5.960 mm (0.2343-0.2346 in) |
EXHAUST | 5.940-5.950 mm (0.2339-0.2343 in) |
Tightening torque
Tightening torque specs | |
Alternator (to cylinder) | 2.0 Nm; 1.5 ft·lb |
Air cleaner base (to carburetor) | 7.0 Nm; 5.2 ft·lb |
Air cleaner support bracket | 7.0 Nm; 5.2 ft·lb |
Armature | 3.0 Nm; 2.2 ft·lb |
Blower housings | 7.0 Nm; 5.2 ft·lb |
Back plate | 7.0 Nm; 5.2 ft·lb |
Breather | 3.0 Nm; 2.2 ft·lb |
Carburetor to manifold | 7.0 Nm; 5.2 ft·lb |
Connecting rod | 13.0 Nm; 6.9 ft·lb |
Crankcase cover | 17.0 Nm; 12.6 ft·lb |
Cylinder head | 19.0 Nm; 14.1 ft·lb |
Cylinder shield | 7.0 Nm; 5.2 ft·lb |
Exhaust manifold | 17.0 Nm; 12.6 ft·lb |
Flywheel nut | 175.0 Nm; 129.6 ft·lb |
Fan Retainer | 17.0 Nm; 12.6 ft·lb |
Governor lever nut | 8.0 Nm; 5.9 ft·lb |
Governor control bracket | 16.0 Nm; 11.9 ft·lb |
Intake manifold to cylinder head | 16.0 Nm; 11.9 ft·lb |
Oil pump | 7.0 Nm; 5.2 ft·lb |
Rewind starter (to blower housing) | 7.0 Nm; 5.2 ft·lb |
Rocker arm lock nut | 7.0 Nm; 5.2 ft·lb |
Rocker arm stud | 11.0 Nm; 8.2 ft·lb |
Starter motor | 16.0 Nm; 11.9 ft·lb |
Starter motor thru bolts | 6.0 Nm; 4.4 ft·lb |
Valve cover | 3.0 Nm; 2.2 ft·lb |
Service Information
Engine | |
Max speed | 3,600 rpm |
Valve clearance | |
Intake valve clearance | 0.10-0.15 mm (0.004-0.006 in) |
Exhaust valve clearance | 0.10-0.15 mm (0.004-0.006 in) |
Oil system | |
Oil type | API SF, SG, SH, SJ or higher |
Recommended oil |
Summer: SAE 30, 10W-30 Winter: SAE 5W-30 |
Oil capacity (with filter) | 1.65 L (1.74 US. qt, 1.45 Imp. qt.) |
Ignition system | |
Spark plug | Champion RC12YC |
Spark plug gap | 0.7-0.8 mm (0.0276-0.0315 in) |
We try to use verified sources and official documentation, however, differences between sources or errors in entering information may occur. We do not provide advice on technical issues related to the engines operation or repair. We do not recommend using provided information for engines repairing engines or spare parts ordering, use only official service manuals and spare-parts catalogs.
Working on a 2015 version of this engine. Had all the parts laid out on a trailer. My kid moved the trailer and the push rods rolled all over the place. This document says they are both the same size. On this engine one is the size specified, the other is much smaller, more like 1/8″. I assembled it presuming the intake was the smaller one. Hoping I’m right about that.
Hi, thank for sharings thoses infos! I restored a wood crusher equiped with that engine.
Would by any chance know the compression value? I measured 9.25 and 9.5 Bar on each cylinder. Thanks for your help
Greetings from Belgium.