[galernikus]

I recently acquired a Yanmar 4JH3-TE with 5000 hours on it. It was used for water taxi and looks like it is in a great shape but 5000 hours is a lot of time and I would like to rebuilt it. I was hoping that someone might have either experience or knowledge about this engine as far what needs to be rebuilt? Anything particular about this engine that goes bad? Seals, rings,pumps etc.?

 

[Gladrags1]

I highly recommend getting the SELOC book which completely covers all issues of this great motor. It will walk you through a rebuild and is a great reference.

Tod

 

[Don L]

I would look at doing an oil analysis and compression test before tearing apart what could be a perfectly fine engine.

 

[miatapaul]

I would look at doing an oil analysis and compression test before tearing apart what could be a perfectly fine engine.

Yea, a water taxi likely ran it for long hours per day, and that does not put much wear on a motor, like starting it and running it for 15 min to get in and out of a slip. Many of these industrial motors will run for 10s of thousands of hours if maintained properly and run continuously. It could well have less wear than a sailboat with 800 hours on it.