A few days ago in this blog, I compared 2-stroke and 4-stroke outboard motors. In the news this week, another question arose. The year 2006 was the original deadline the Environmental Protection Agency (EPA) gave for all outboard motors in use to meet new, more stringent emission requirements-levels so low that many consumers believed that 2-stroke motors would have to be done away with altogether, simply because they did not have the technology the EPA guidelines would require. However, almost three years later, two-stroke outboard motors are still being sold, even though statistics have shown that up to 40% of the gas and oil in a two-stroke motor’s gas tank enter the water unburned. One study suggests that a 70-horsepower outboard motor emits as many hydrocarbons per hour as the average automobile driven about 5,000 miles.
There are currently no regulations demanding the disposal of two-stroke outboard motors, which are still acceptable in all but a very few situations. Some of these motors are over 25 years old and still running smoothly, but their overall fan base is dwindling due to environmental concerns. The real issue is not with all two-stroke motors, but with the older models that are not directly oil- or fuel-injected, where the outboard motor oil and fuel are mixed in a can prior to use.