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Can You Use TruFuel In A Lawn Mower?

Can You Use TruFuel In A Lawn Mower?

TruFuel is a range of ethanol-free fuels mixed with a certain proportion of lubricants, stabilizers, and detergents, made for the smaller engines of outdoor power equipment, including lawn mowers. This fuel mixture helps 2 or 4-cylinder engines run smoother, stay cleaner, and they spare you the task of mixing fuel with conditioners yourself. 

Is TruFuel The Same As Gasoline?

TruFuel Pre-Blended 2-Cycle Fuel for Outdoor Equipment - 32 oz. (2-Pack, 50:1)

TruFuel and other engineered fuel products contain gasoline as well as other additives that help maintain the engine’s performance and condition. Gasoline at the pump often contains ethanol, an alcohol that is meant to support fuel efficiency in cars. Pure gasoline is just fuel, without conditioners added. 

Pre-mixed Fuel Formulas

TruFuel mixes come in different gasoline-to-oil ratios, which, if you purchased pure gasoline, you’d have to mix yourself. That’s one of the appeals to TruFuel and other engine fuel mixes. The pre-measured portions of gasoline-to-oil, as well as the lubricants and detergents that are added, save you the time and effort of keeping and mixing these different ingredients.

The mixes come in 40:1, 50:1, or 4-cylinder blends, which all are specific to certain kinds of engines. 40:1 has a lower proportion of oil than 50:1, which refers to the parts of gasoline (the first number) to the parts of oil (the second number). 

A 4-cylinder engine doesn’t use the same type of fuel-to-oil mixture that 2-cylinder engines do. A 2-cylinder engine requires 2 strokes of the piston system to intake air and fuel for the combustion process. They’re smaller and less powerful than 4-cylinder engines, although either can be used for lawn care machinery. 

A 2-cylinder engine uses a fuel and oil mix to lubricate itself for peak performance, but a 4-cylinder engine has separate tanks for gasoline and for motor oil. If these are mixed and put into a 4-cylinder engine, it will smoke and overheat.

TruFuel 4-Cycle Ethanol-Free Fuel for Outdoor Power Equipment - 32 oz. Pack of 2

Octane Rating

Gasoline comes with an octane rating between 87 and 94. The number refers to its ability to withstand compression pressure when the fuel-to-air mixture is pulled from the carburetor into the combustion chamber.

When high compression engines are given a gasoline octane lower than what’s recommended, the fuel may detonate before the piston cycle is finished, which results in the pinging and banging that may be heard in engines that are given, for example, a regular or midgrade fuel in an engine that requires premium. 

TruFuel is made with 92+ octane gasoline, which has a high range of lean to rich burning tolerance in engines, providing good performance and fuel economy. An engine is running “lean” when it has a high air-to-fuel ratio (more fuel efficient), which can be adjusted by the choke. When an engine is running rich, it’s burning more fuel with less air, making it less efficient with the potential to overheat. 

Ethanol In Gasoline

Ethanol is an alcohol made from corn and is a cleaner-burning biofuel alternative to gasoline that can be added to gas to lower carbon emissions from cars. Small engines, like those used in lawn mowers and other smaller yard care equipment, aren’t designed to run with ethanol alcohol fuel. TruFuel formulas are ethanol free, while some pump gas is and others aren’t.

This is important because, these days, gasoline that you buy from gas stations is frequently diluted with ethanol to contribute to reducing car emissions. New cars are designed with engines that can tolerate an ethanol mixture, but it can pose serious performance problems for smaller yard equipment engines and lead to the need for major repairs:

  • Engine buildup –As an alcohol, ethanol is also a cleaning agent and lifts buildup in engines, but doesn’t break the material down. Rather, the solids build up faster in fuel lines and jets, interfering with fuel delivery and ignition.
  • Overheating – The alcohol burns at a higher temperature than gasoline, which can weaken the engine’s metal if it raises the temperature enough. In addition to engine damage, overheating can lead the engine to stall or die.
  • Water collection – Ethanol molecule chains bond with water vapor from the air, which collects and leads to water buildup. The longer that fuel tanks are stored with ethanol gasoline, the more water that collects. Water isn’t good for engines: when it’s mixed with fuel, it sinks to the bottom of the tank and is pulled into the engine without fuel. This results in compression issues that can cause severe damage to the engine. 

Storing Gasoline And TruFuel

Neither pure nor ethanol gasoline can be stored for a very long time, going bad after about a month; you should only use fresh fuel in engines. As a volatile substance, the components separate quickly: the liquids evaporate and the solids settle and stick together. 

TruFuel is made with synthetic fuel stabilizers that keep the fuel fresh for longer by preventing oxidation, or the breakdown of the gasoline components from exposure to air. It has a shelf life of 5 years unopened, and up to 2 years once you start to use it. 

What Fuel Should I Use In My Lawn Mower?

Putting Fuel In Lawn Mower

Depending on whether you have a 2-cylinder or 4-cylinder engine on your mower, ethanol-free gasoline, a gasoline and oil mix, or an engineered fuel like TruFuel may be your best choice. Always read your lawn mower’s manual to know what kind of fuel or alternate fuels the manufacturer recommends. 

A 4-cylinder engine will do best with pure, ethanol-free gasoline in the fuel tank and oil in the lubricant tank, or with a TruFuel 4-cylinder formula. If your mower has a 2-cylinder engine, a 40:1 or 50:1 TruFuel mix is the best option if you don’t want to mix the oil and gas yourself.

The TruFuel formulas also improve engine performance with their cleaning agents, a feature that can improve the lifetime run quality of your equipment. 

TruFuel 4-Cycle Ethanol-Free Fuel for Outdoor Power Equipment - 32 oz. (Case of 6), grey (6527238-6PK)
  • Pre-blended for outdoor power equipment - TruFuel provides the perfect fuel for all 4-cycle
  • For use in 4-cycle engines
  • Specifically for portable gas-powered equipment - convenient, saves time and delivers superior...
  • Reduced aromatics and consistent vapor pressure lead to a cleaner burning fuel with the addition of...

Last update on 2022-07-05 / Affiliate links / Somes Images and Data from Amazon Product Advertising API