We own a 2003 DF 90 w/300 hours that has been serviced on schedule by Suzuki dealers and had the impeller replaced biannually. It is garaged between uses and was winterized and garaged in fall of 2010 in great shape. As soon as it went into water this spring, it immediately had a louder than normal exhaust noise upon starting. Suggestions? Is it safe to run until it's repaired?