The carbon canister works to absorb diurnal vapors. When the engine runs, an intake vacuum draws any vapor from the tank into the engine, where it is burned. After the engine is shut off, vapors continue to be emitted into the atmosphere due to temperature changes throughout the day. The carbon canister absorbs those vapors, and when the engine is started again, the engine intake vacuum will draw in fresh air through the carbon canister’s vent port and thus purge the stored vapors.
Some engine manufacturers also are incorporating optional vapor control valves in new systems. These devices prevent liquid fuel from getting into the vapor system. Originally developed to prevent fuel leakage during rollover accidents, these also might be referred to as “rollover valves.”
What’s now required
Beyond making the adaptations to the new systems to limit evaporative emissions, OEMs must complete several steps to ensure adherence to the EPA’s regulations. This includes registering through the Verify system, labeling engines according to the standards, and providing emissions-related warranties. This all effects the look of new equipment, as well as adding new warranty guidelines of which consumers should be aware. A basic understanding ensures generators and other small-engine-driven equipment will last for year’s to come.
The EPA’s Verify information system collects data on emissions and fuel economy compliance for all sizes of engines. Each manufacturer must register with the EPA and apply for evaporative certification for its equipment through Verify. Manufacturers cannot sell equipment until obtaining the certificate through Verify, so rest assured that any new equipment purchased will meet the new standards.
Under the new regulations, manufacturers also will need to place an approved evaporative emissions label on the equipment. This label must be permanently affixed or engraved on the engine and will include the heading “EMISSION CONTROL INFORMATION.” It will be followed by the manufacturer’s corporate name and trademark, the EPA’s standardized designation for the emission family and the date of manufacture. The EPA also requires that the label include the emissions compliance period, in hours, over which the engine exhaust emissions system was tested. A statement certifying that the engine meets exhaust emission regulations also must be included. While more information can be added, the above is what’s required on any small engine-operated equipment now manufactured and sold in the United States, so expect to see it on any new purchases.
Each piece of new equipment also must come with an approved evaporative emissions warranty statement. Under this requirement, consumers purchasing the equipment, along with each subsequent buyer, will know that the engine, along with all of the parts of its emission control system, meets two conditions. First, at the time of sale the engine is designed, built and equipped to meet EPA regulations and, second, that there are no defects in the workmanship or materials that would keep the engine from meeting emission standards.
The EPA requires a minimum two-year emission-related warranty, although exceptions are made for some hand-held engines used in more intense, seasonal service. The warranty covers any component that, should it fail, would increase the engine’s emissions of a regulated pollutant. Manufacturers will spell out all of the warranty details in the owner’s manual and provide a toll-free phone number and email address so that consumers can quickly file a warranty claim and have authorized repairs made so that they are not without their tools for long.
What can’t be done
With these new standards in place, it’s no surprise that some things now can’t or shouldn’t be done with generators and other small-engine equipment.
First and foremost, don’t tamper or attempt to modify engines designed to meet EPA standards. Not only is it illegal and comes with civil penalties, but it can cause a host of problems. For example, removing an engine’s vapor control valves presents a fire hazard and can cause liquid fuel in the vapor system to severely damage the carbon canister.
Knowingly disabling an emission control system component, from tweaking the fuel or exhaust system to altering the engine’s performance, will violate the EPA regulations. Installing a part that differs from that originally on an engine that meets EPA standards also may bring penalties for tampering.