Is this a 2-cycle engine? If so, what is the best oil gas ratio?

Briggs and Stratton manufactures both 2-cycle & 4-cycle engines. Two-cycle engines are able to propel your lawn mower, snow blower or pressure washer in one crankshaft revolution and two strokes of the piston. The vast majority of the small engines Briggs & Stratton manufactures are 4-cycle engines, which require four strokes of the piston to complete a crankshaft revolution.

In this FAQ, you’ll learn:
How to Identify a 2-Cycle Small Engine
How To Determine the 2-Cycle Engine Oil Mix

The easiest way to determine if your small engine is a 2-cycle or 4-cycle is the number and type of fill ports (where you add either oil or gas) on the engine. Compare your gas cap and/or oil port with the images below.

• If the engine has a single fill port for both the small engine oil and gas, you have a 2-cycle engine.

• If the engine has two fill ports, one for gas and another separate fill for oil, you have a 4-cycle engine. Do NOT mix oil and gas in these engines.

The following 2-cycle stroke engine series was provided to outdoor power equipment manufacturers until about 1991:

• 62030 to 62033
• 95700 to 95799
• 96700 to 96799

In addition, Briggs & Stratton has recently begun manufacturing the following model series for 2-cycle snow blower engines:

• 84100
• 84200
• 84300

To determine if your engine model number is listed above, please check out The Your Small Engine Model Number page.

Since all 2-cycle small engines use the same fill port for both fuel and oil, a 2-cycle oil mix is necessary for your outdoor power equipment to function properly. The Specific oil/gas ratio for your lawn mower, snow blower or power washer can be obtained in your Operator’s Manual. Once you identify your oil/gas ratio, the following chart may be helpful, providing two common oil to gas ratios used in 2-cycle Briggs & Stratton engines.

50:1 Ratio

32:1 Ratio

Still need help? Contact a Briggs & Stratton dealer for assistance.