My 18 year old
Yanmar 4Jh2E (53HP) with 4200 hours is blowing a good deal of
exhaust out the
oil fill hole and there is a “sheen” in the
water when I start it up. For the most part,
engine runs smoothly, uses no
oil and starts immediately every time – there is a slight vibration at higher RPM’s (2650) and a “different” sound – this could be nothing more than my own paranoia... Last Spring I had an oil cooler fail and filled the
engine with
salt water (2nd time this has happened). I replaced the oil cooler, flushed the engine with
diesel and multiple gallons of oil in a
remote part of
Mexico (very fun…). On my way back to
California from
Mexico, the engine developed an
oil leak on the front main seal. When changing this I discovered the front pulley had a great deal of rust on the portion that is inside the seal. I replaced the pulley (too pitted to reuse) along with the seal – all is good now. But, it seems, the engine is on its way out and I don’t want to deal with this in an unplanned “we have a situation” way. In researching choices I’m not sure if I should replace with the
Yanmar 4JH5E (53HP) or the 4JH4-TE (75HP). Doing the
hull speed and “Gross Weight/500 LBS” calculations puts me at needing 62HP. There isn’t much weight difference between the engines and the
fuel economy would be about the same according to the
research. Not real excited about having the turbo (heat and TLC needed) however I’m sort of drawn to the added HP for coming north bound trips from Mexico. I would greatly appreciate any thoughts/comments. Thank you