I inherited my Father-in-laws 2004 325 with 1400 hours which has been a great machine. Started getting a severe mower deck vibration which damaged several of the belt tension mechanisms during the last couple years. That issue was followed by a major oil leak this Spring. I decided to attempt my first engine rebuild. Removed the engine, cleaned it up, honed the cylinders, installed new rings, redid the valves, installed all new gaskets, cleaned the carb and reassembled. Every step was a learning experience made much easier with YouTube and the Kawasaki manual I found online. It took me quite awhile to first learn then due each piece of work. The engine really accumulated dirt and grime over the years, as you can see in some of the pictures, which I failed to address. I wonder if the engine began overheating as all the cooling fins were plugged which might have led to the oil leak. I had the crankshaft dimensions checked to ensure it was not bent enough to cause the mower deck vibration. Everything checked out.
You can see in the pictures below that the PTO hole was widened quite a bit from vibration. In addition, the post that the hole fits on was severely worn with half the diameter missing. I filled the post void by mig welding then ground it back to normal shape. I then welded a wash on top of the pto to close up the hole. I hope this was causing the vibration problem.
The engine started right up which was awesome. It did race significantly so I worked to get the governor adjusted. This took sometime to understand and once fixed worked with the low and high idle per the manual.
Snowblower is now on and the pto works which is great. It will be interesting to see what happens when the mower deck goes back on.
Great learning experience.