What is your opinion ? I bought this mower new in 2001 and the 23 kaw is showing its age finally. Bad oil leak with some backfiring and popping at times when cold starting. Does run strong though. The original blade spindles are still tight. The hydro's are still good and strong. Mower is in decent shape still for its age Is it worth looking into a rebuild or should I just replace the engine with a new one ? Should I upgrade to a bigger engine. The 23 Kaw has always done me good. Where have you bought your complete engines at ? Do they sell them has long blocks and short blocks ? is there a write up some where on the removal and install.