Re: 1993 yamaha 225 outboard
Water can be getting in thru the exhust .The plate on the backside of your eng.between the heads has water passages that allow cooling to exhust areas.Its not uncommon,what happes could be the result of heat ,warping a surface ,or corrosion,if your POSITIVE that its not a head.cyl block seal problem,I would look there.Removing all the bolts and pulling the plates to see what it looks like.Another possibilitiy ,is the cyl head seal.Often the surounding alum cast,that encapsules the cyl.sleeve can corrode away,allowing only the sleeve to seal the head/cyl area.this becomes too small a seal.Another problem falls when people decide to put a bracket on their hulls.allowing the motor to side back of the transom.What happens here is geometry.The further back the engine,the center of gravity then allos the eng to get dunked,water then reaches its level inside the eng ,causing water to enter thru the exhust ports.I saw many newer engins get toasted because home mechanics didnt allow for this problem.Especially with OLDER NON BOUYANT BRACKETS.
