I've read a lot of posts about JohnyRude 9.5 hp engines and their exhaust leaks, causing engines to stall. Sounds like some years/models are more prone than others, and some are harder to fix than others. I'll be looking at a 1973 Evinrude 9.5 hp this weekend. The model number is 9322B, and the serial number is J 07865. <br /><br />Can someone explain which ones are vulnerable, and why? Which are hard to fix and why?<br /><br />THANKS