Specifications

CAUTION

All the components used to build this engine assembly must remain in place for the proper operation of this engine.

We recommend that you use an authorized Briggs & Stratton Service Dealer for all maintenance and service of the engine and engine parts. Use only genuine Briggs & Stratton parts.

GENERAL INFORMATION

This is a single cylinder, air-cooled engine. It is a low emissions engine.

In the state of California, Model 21000 and 21100 engines are certified by the California Air Resources Board to meet emissions standards for 50 hours. Such certification does not grant the purchaser, owner or operator of this engine any additional warranties with respect to the performance or operational life of this engine. This engine is warranted solely according to the product and emissions warranties stated elsewhere in this manual.

Model 21000

Bore . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.575 in. (40 mm) Stroke . . . . . . . . . . . . . . . . . . . . . . . . . . 1.065 in. (27 mm) Displacement . . . . . . . . . . . . . . . . . . 2.074 cu. in. (34 cc)

Model 21100

Bore . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.575 in. (40 mm) Stroke . . . . . . . . . . . . . . . . . . . . . . . 1.250 in. (31.75 mm) Displacement . . . . . . . . . . . . . . . . . . . 2.44 cu. in. (40 cc)

Note: For practical operation, the horsepower loading should not exceed 85% of rated horsepower. Engine power will decrease 3-1/2% for each 1,000 feet (300 meters) above sea level and 1% for each 10° F (5.6° C) above 77° F (25° C).

Tune-Up Specifications

Armature air gap . . 0.010 − 0.014 in. (0.25 − 0.36 mm)

Spark plug gap . . . . . . . . . . . . . . . . . 0.025 in. (0.64 mm)

Valve clearance with valve springs installed and piston 1/4 in. (6 mm) past top dead center (check when engine is cold). See Repair Manual P/N 271172.

Intake . . . . . . . . . . . . 0.002 − 0.004 in. (0.05 − 0.10 mm) Exhaust . . . . . . . . . . 0.002 − 0.004 in. (0.05 − 0.10 mm)

Model, Type and Code Number

To get replacement parts or technical assistance in the future write your engine Model, Type and Code number along with the date of purchase here. These numbers are located on your engine. For the location, see page 3, Engine Features.

Model
Type
Code

Technical Information

Engine Power Rating Information

The gross power rating for individual gas engine models is labeled in accordance with SAE (Society of Automotive Engineers) code J1940 (Small Engine Power & Torque Rating Procedure), and rating performance has been obtained and corrected in accordance with SAE J1995 (Revision 2002-05). Torque values are derived at 3060 RPM; horsepower values are derived at 3600 RPM. Actual gross engine power will be lower and is affected by, among other things, ambient operating conditions and engine-to-engine variability. Given both the wide array of products on which engines are placed and the variety of environmental issues applicable to operating the equipment, the gas engine will not develop the rated gross power when used in a given piece of power equipment (actual “on-site” or net power). This difference is due to a variety of factors including, but not limited to, accessories (air cleaner, exhaust, charging, cooling, carburetor, fuel pump, etc.), application limitations, ambient operating conditions (temperature, humidity, altitude), and engine-to-engine variability. Due to manufacturing and capacity limitations, Briggs & Stratton may substitute an engine of higher rated power for this Series engine.

Emission Information

Engines that are certified to meet the California Air Resources Board (CARB) Tier 2 Emission Standards must display information regarding the Emissions Durability Period and the Air Index. Briggs & Stratton makes this information available to the consumer on our emission labels. The engine emission label will indicate certification information.

The Emissions Durability Period describes the number of hours of actual running time for which the engine is certified to be emissions compliant, assuming proper maintenance in accordance with the Operating & Maintenance Instructions. The following categories are used:

Moderate: Engine is certified to be emission compliant for 50 hours of actual engine running time.

Intermediate: Engine is certified to be emission compliant for 125 hours of actual engine running time.

Extended: Engine is certified to be emission compliant for 300 hours of actual engine running time. For example, a typical walk-behind lawn mower is used 20 to 25 hours per year. Therefore, the Emissions Durability Period of an engine with an intermediate rating would equate to 10 to 12 years.

Certain Briggs & Stratton engines will be certified to meet the United States Environmental Protection Agency (USEPA) Phase 2 emission standards. For Phase 2 certified engines, the Emissions Compliance Period referred to on the Emissions Compliance label indicates the number of operating hours for which the engine has been shown to meet Federal emission requirements.

For handheld engines:

Category C = 50 hours

Category B = 125 hours

Category A = 300 hours

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