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Upgrade octane in fuel
for 2-cycle engines
Would you spend 10 cents a gallon per unit to make your string trimmers, blowers and chain saws last longer and perform better?
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Stepping up to higher-octane fuel may cost more, but |
How is this possible? Start using higher-octane gasoline for your 2-cycle oil-fuel mix. Check your operator manuals. You’ll find that most makers of 2-cycle engines call for 89 octane gasoline. Chances are this mid-grade fuel costs about 10 cents a gallon more than the basic 87-octane “regular” grade sold throughout most of North America.
The higher octane does not give you more power, but it does reduce pre-ignition (commonly called “knocking” or “pinging”).
Pre-ignition occurs when the fuel-oil-air mix in the cylinder starts burning before it is supposed to. The cloud of burning, expanding gas slams against the piston while it is rising in the cylinder to compress the fuel charge. You can hear pre-ignition in a well-muffled car or truck. But your ears are not likely to sort it out from the typically high-pitched exhaust noise from a 2-cycle engine.
Severe pre-ignition can break the connecting rod, destroy rod bearings and/or score the piston and cylinder walls by cocking the piston in the cylinder bore. Even light pre-ignition is bad for the engine’s life and performance.
Higher-octane fuel is less likely to ignite when the temperature of the fuel-air-oil charge naturally increases when it is compressed by the rising piston. The hotter the engine, the more likely the pre-ignition.
Several factors work to raise cylinder temperatures:
• Hot outdoor temperatures
• Plugged cooling fins
• “Lugging” the engine (for example, bearing down on a dull chain saw), which slows the engine cooling fan at the same time it makes the engine work harder and hotter
• Emission control laws, which have led to leaner, hotter-burning fuel/air ratios
• Thinner fuel/oil loads (50:1 instead of 16:1), which yield higher combustion temperatures
Small air-cooled engines don’t have the knock sensors and computerized engine controls that adjust ignition timing and fuel flow to limit pre-ignition in modern cars and trucks.
Instead, the manufacturers of turf equipment trust the end-user to use the specified higher-octane fuel, along with the correct type and ratio of oil, to keep the little 2-cycle engine fleet in proper operation without pre-ignition.
Higher octane won’t necessarily reduce incorrect ignition caused by a hot chunk of carbon or an overheated spark plug tip. Such hot spots produce “dieseling,” when the engine keeps running after you turn off the ignition.
NoiseBuster active noise reduction safety earmuffs from Pro Tech provide hearing protection for industrial workers and users of power tools and other loud machinery. Unlike traditional earmuffs and earplugs, the NoiseBuster offers protection from a wider range of noise frequencies, particularly those generated by engines, motors and fans, the company says. The passive component of the NoiseBuster earmuff features a noise reduction rating of 26 dB, and the active noise reduction component provides as much as 20 dB of added noise reduction within the low-frequency bandwidth of 20-800 Hz. Contact Pro Tech Communications Inc., 877-226-1944 (www.noisebuster.net). A new wear-time evaluation tool from Howard Leight by Sperian Hearing Protection LLC identifies the optimum amount of attenuation a hearing protection device will provide over an 8-hour shift if removed for various lengths of time. The disk-shaped device, available free from the company to safety officers and educators, also offers advice on how to select the proper hearing protector. The outer ring of the larger disc shows a range in decibel levels of attenuation provided by various hearing protectors, and the small disc shows time increments of five, 10, 15 and 30 minutes. To learn more, contact Sperian Customer Care, 800-430-5490.
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