I have had an '93 used Suzuki 25 HP for 6 years now, mainly used for duck hunting and it has been to heck and back. Spun the hub this year for the first time (prop that came on the motor), I replaced it with one of those Vortex exchangeable hub insert props so if it hppens again all I have to buy is a ~$40 insert.
If you're not hitting anything, and the motor has through hub exhaust, too high exhaust gas temperatures is usually the cause of hub failures. High exhaust temps are caused by motors jetted to run very lean, or by dirty carbs with jets partially blocked. Neither condition is good for the longevity of the motor. Might be time to run some QuickClean or similar through the motor, or teardown and rebuild the carbs. BillS
Just had a problem we fixed with a friends motor real similar to this, he kept spinning hubs on his 90 V4 OMC. Found out he had the wrong spacer/thrust washer behind the prop. As near as we can tell, the splines in the hub were taking all the load versus the back face of the prop transferring load from the prop to the shaft via the taper the spacer bears against. Put the right spacer in, and no more problems.