Last fall my 50hp blew a piston ring..The Problem Ended up being the recirculating system was 95% clogged causing a lean condition..With a good manual, mechanical skills and most importantly, the iboats force forum; I rebuilt the motor and it runs better than ever..I wanted to thank all the regular posters and especially Frank Acampora, JerryJerry05. Hats off to you fellas. Thanks for your patience and sharing your wealth of knowledge...See you on the water... Chris