1995-1997 Kawasaki 750ZXi-900ZXi Jet Ski Repair Manual., Page 105Get this manual
7-16 ENGINE BOTTOM END Crankshaft Maintenance
The crankshaft changes the reciprocating motor of the piston into rotating motion to drive the jet pumpCrankshaft trouble, such as excessive play or runout, will multiply the stress caused by the intermittent force on the piston and will result in not only rapid crankshaft bearing wear, but also noise, power loss, vibration, and shortened engine lifeA defective crankshaft should always be detected at an early stage and repaired immediately The following explanation concerns the most common crankshaft problems and the method for measuring play, runout, and con-rod alignment, it does not cover crankshaft disassembly because of the highly specialized equipment that is required If crankshaft components become damaged or worn, the entire shaft should be replaced as an assembly, or rebuilt by properly equipped shop
Connecting Rod Bend Twist
OSet the crankshaft in an alignment jig or in blocks on surface plate Select an arbor of the same diameter as the connecting rod small end and at least 100 mm long, and insert the arbor through the connecting rod small end0 With the connecting rod held vertically, use height gauge to measure the difference in the height of the arbor above the surface plate over 100mm length to determine the amount of connect rod bend If connecting rod bend exceeds the service limit, the connecting rod or crankshaft must be replaced Connecting Rod Bend Standard: Under 0.05100 mm Service Limit: 0.21100 rnm