1992-1998 Kawasaki PWC Jet Ski Service Repair Manual., Page 33Get this manual
MAINTENANCE
bladesThe edges of the blades may develo small "dime size" resembling porous sponge, as the aluminum is actually "eaten" by the condition just describedExcessive rounding of the impeller edges will reduce efficiency and performanceTherefore, the impeller should be inspected at regular intervalsIf rounding is detected, the impeller should removed from the housing, placed on work bench and the edges restored to as sharp condition possible using fileRefer the Jet Pump chapter for detailed procedures on removal and installation of the impeller
4-2 SERIAL NUMBERS
Most manufacturers use three different identification numbers stamped, embossed or decaled somewhere on the craftThe engine serial number is the manufacturer's key engine changesThis number identifies the year of manufacture, the qualified horsepower rating, and the parts book identificationIf any correspondence or parts required, the engine serial number MUST be used or proper identification is not possibleFederal regulations require all personal to have Hull Identification Number (HIN)permanently attached the craft in two separate locations: one on the transom on the starboard side, waterline and the other in an unexpos location, which is usually left to the discretion of the manufacturer This "HIM" number can most helpful when atternpting retrieve stolen craftThe "