Proper time on your Briggs & Stratton 15 motor engine is vital for peak engine performance and proper engine operation. Briggs & Stratton 15 horsepower engine ignition systems consist of an ignition armature and breaker points. These features work with the flywheel to ship a spark sign to the spark plug at the peak of the engine compression stroke, which ignites the fuel and air mixture in the engine cylinder. These parts must be secured with each other for proper engine operation.
Drain any excess fuel from the engine fuel tank to prevent fuel spillage. Unscrew the engine cover shroud retaining screws, if equipped, from the engine assembly with a screwdriver to access the engine blower housing. A few 15 horsepower Briggs & Stratton engines require that the fuel tank to be removed before removing the engine blower housing.
Pull the spark plug high-tension direct from the spark plug, or using crank plug pliers for adhered high-tension leads. The spark plug is found in the engine cylinder head in the front or back of the engine crankcase.
Unscrew the spark plug from the engine cylinder having a 5/8-inch spark plug socket wrench. Unscrew the air filter housing cover retaining screws with a screwdriver. Boost the air filter housing cover and air filter element from the air filter housing. Unscrew the air filter housing retaining screws from the engine assembly with a screwdriver.
Unscrew the oil filler tube retaining screw from the engine blower housing with a socket wrench, if equipped. Unscrew the engine blower housing retaining bolts from the engine assembly with a socket wrench. Boost the engine blower housing from the engine assembly. A few 15 horsepower Briggs & Stratton engines are equipped with outside breaker points that must be assessed and adjusted occasionally.
Loosen the ignition armature mounting screws with a socket wrench. Pull the armature back away from the flywheel and tighten among the mounting screws to hold it in place when correcting the flywheel.
Expand the flywheel to align the flywheel magnet with the ignition armature legs. Put a 0.08- to 0.012-inch feeler gauge tool involving the flywheel magnet and ignition armature legs to adjust the ignition armature air-gap for good ignition timing.
Loosen the ignition armature mounting screw having a socket wrench to permit the flywheel magnet to pull the ignition armature legs into the feeler gauge tool.
Torque the ignition armature mounting screws to 25 inch-pounds with a torque wrench and socket. Expand the flywheel to remove the feeler gauge tool from the ignition armature legs. A few 15 horsepower Briggs & Stratton engines are equipped with just an armature type ignition, so the ignition armature air-gap is the only timing adjustment demanded.
Unscrew the breaker point housing cover retaining screw with a screwdriver to access the ignition breaker points. Rotate the engine flywheel before the breaker point contacts are fully opened. Loosen the breaker point adjusting screw and locknut with a wrench. The adjustment screw and locknut are found just before the breaker point contacts.
Insert a 0.20-inch feeler gauge tool involving the breaker point contacts. Turn the breaker point adjusting screw with a flathead screwdriver clockwise to raise or counterclockwise to decrease the breaker point contact gap. Tighten or loosen the breaker point adjusting screw until the breaker point contacts fulfill the feeler gauge tool.
Tighten the breaker point adjusting screw locknut with a wrench. Eliminate the feeler gauge tool from the breaker point contacts. Slide it back in place a couple of times to check for proper adjustment — it must fit between the breaker point contacts with slight drag.
Reassemble the engine in reverse order of disassembly. Start and stop the engine several times to check for proper engine ignition adjustment. The engine should run smoothly with no misses or surges when the ignition timing is correctly adjusted.