The Briggs and Stratton 386777 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 386777 engine has an OHV (overhead valve) design and a vertical PTO shaft. This engine is equipped with float type, side-draft carburetor and an electronic ignition system. The B&S 386777 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; 23.0 HP) at 3,600 rpm of horsepower.
The breakdown of the engine code is as follows:
- 38 – Displacement
- 6 – Basic design series
- 7 – Vertical PTO-shaft
- 7 – Plain bearing, Pressure lubrication
- 7 – Electric starter
General information
| Engine Specifications | |
| Model | B&S 386777 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) |
Author:
hello
great site! I am searching for the engine torque spec for a vanguard 3867 engine but cannot find it detailed anywhere, do you know where i can find it? and why its not detailed as it I want compare motors