What does rebuild actually mean?

[dlj]

Originally Posted by MJH

Given two boats exactly the same except for the engine, one make and model that sold 10-20 years prior and has been rebuilt and the other with a new engine I know which one I would pick. There is more to the engine rebuild/replacement decision than life expectancy, even giving a rebuild the benefit of the doubt.

I'd want to know who did the rebuild.

Given we used to rebuild engines for high performance applications - I'm definitely in the "rebuild them right" camp and they are better than new...

dj

[Shaneesprit]

Originally Posted by rockin411

I've posted a few recent threads about my 1 cylinder Yanmar SB12 and am thinking of going down that path. If I do I'm hoping to raise it up in the boat and rebuild there. What do people mean when they say rebuild? Is it just new rings, new cylinder sleeve, valves and that's it? What else should be done?

Fully strip engine clean and replace all gaskets and bearings, piston rings, as a minimum, anything else is just a repair.
I could easily do this but I wouldn’t, far better to just have an Engine specialist rebuild it, plus they will be able to measure and polish far better than can be managed by diy.
I would only do this if I really wanted to and would still get some parts done in a specialist.
Also replace the injector.

[Ballsnall]

Originally Posted by Shaneesprit

Fully strip engine clean and replace all gaskets and bearings, piston rings, as a minimum, anything else is just a repair.

Don't forget the head job (valve regrind, guide's and seals) heads commonly wear more than the lower block components. Best done by a machine shop as it requires specialised equipment. The rest of the rebuild is mainly just parts change out. No difference between an engine specialist and DIY for small engines, you don't even need any qualifications as an engine rebuilder.