Introduction

According to the Izaak Walton Leaque of America, one of the  most highly polluting carbureted engines, the two-stroke engine, is utilized by 75 percent of all Personal Watercrafts (PWC) and causes water pollution. In a single days use, PWCs may emit the same amount of hydrocarbons and nitrogen oxides as a 1998 passenger car driven 100,000 miles. This pollution has significant effects on wildlife. Industry officials concede that at least 25 percent of fuel escapes in emissions, but they claim that no lasting environmental harm can be linked to PWC usage.

Due to the design inefficiency of two-stroke engines, 1.1 billion tons of hydrocarbons are emitted per year in California alone.Gasoline constituents emitted by PWCs include carcinogenic benzene, toluene, and also xylene. These constituents floating on the water's surface, eventually settle within shallow water ecosystems where aquatic life is often undeveloped and vulnerable. The pollution from the fuel bioaccumulates, harming not only the lowest part of the food chain, but also the highest. PWCs also release MTBE and as a Class C carcinogen, MTBE has been detected in drinking water, leading to the restriction of two stroke watercrafts on effected waterways.

It is estimated that the oil burning outboard engines used in PWCs spill 15 times more fuel into U.S. waters each year than the Exxon Valdez, a pivotal oil spill in Alaska during the 1980s that caused major damage to the environment. For one gallon out of every four, unburned fuel is discharged directly into the water.With consumption rates as high as ten gallons per hour; about two and a half gallons of unburned fuel may go into the water each hour. Having twice the hourly annual usage rate as any other watercraft, double the load factor, and significantly more horsepower than a typical two-stroke outboard motor, PWCs emit eight times more pollution than equivalent motorboats.

Pollution from two-stroke engines on personal watercrafts is becoming more extensive, and that is why we have chosen it as the basis of our project. Something must be done to stop the pollution before it is too late and precious lakes, water basins, parks, off-shore ocean waters and wildlife are lost. The carbureted two-stroke engine has been virtually unchanged for 40 years, and the time has come to make significant changes to it. We know we cannot remove personal watercrafts from the waters, but we can make their engines more environmentally friendly and more efficient. We will present background information regarding environmental impacts of MTBE pollution, legal regulations governing the use of personal watercrafts, the background of fuels and additives, and the history and the future of two-stroke engines and the personal watercraft in our project. We will also present modifications to existing two-stroke engines that would help move them towards meeting the new Environmental Protection Agency's emission levels of 2006.