Researchers in midst of E15 engine study

By Holly Jessen | August 27, 2010
Posted Sept. 21, 2010

Several months into a year-long study on the effects of E15, researcher Craig Hoff just doesn't see how the U.S. EPA can make a decision on higher ethanol blends by this fall. "Too many technical questions have not been answered," he said, "and it takes time to organize and run the studies."

Hoff and Greg Davis, both professors of mechanical engineering at Kettering University, are using a $125,000 U.S. DOE grant to study the effects of E15 on mid-1990 era vehicles. Testing started in May, with a minimum goal of 800 hours. "We are likely to have many additional hours, assuming that we don't run into any difficulties," Hoff said.

The E15 study is one of many others currently under way. In fact, it's "a very small piece of a much larger plan," he said.

The EPA has already delayed approving E15 twice. It previously indicated that a decision would be made this fall, perhaps beginning with model year 2007 and newer in September and 2001 and newer in November.

Hoff is one of those recommending caution before moving to E15. Although he's "optimistic" that most fuel systems will work fine with E15, he's advocating a slow and careful approach to avoid potentially costly mistakes. Still, that doesn't mean he isn't an ethanol supporter. "I personally think that moving from E10 to E15 is a good idea for helping to make the country more energy independent," he told EPM.

Researchers will test the fuel components of the Chevrolet Lumina, Ford Taurus and Toyota Camry, one set with E10 and the second with E15. The study uses test rigs, or stainless steel storage tanks with sensors to monitor fuel temperature, flow rate and pressure, to test for signs of damage in the fuel pump and injectors. "We'll be monitoring the pump flow rate and pressures while the system is operating, to be sure that the pumps are operating properly," he said. "Periodically, we'll take the fuel injectors off the test rig and test their operation on a fuel injector test bench. Upon completion of the testing, we will be examining all of the parts for visible signs of damage."

Following the conclusion of testing in May 2011, the researchers will submit a report to the DOE. They also plan to publish a paper through the Society of Automotive Engineers.

This isn't the first time Hoff has studied the effects of ethanol blends on vehicles. A previous study concluded that E10 was safe for use in classic cars, as long as the vehicles have rebuilt carburetors using modern seals and gaskets and that owners regularly monitor for fuel leakage. "When we inspected the parts after testing, we found some minor issues, [such as] minor tarnishing, but nothing suggested the imminent failure of the components," he said. He also added that most classic cars already have rebuilt carburetors and that if a classic car owner doesn't regularly monitor for fuel leakage, they should.