Re: Perkins 4.108M DIY Rebuild -- A Narrative
A few cents of experience;
Taking the block & head castings to an engine shop and having them hot tanked is a bunch easier and more effective than doing it yourself - all the little passages & hidden corners get cleaned and most of the old paint gets boiled off.
Spray Nine works incredibly well on aluminium parts - cylinder head carbon just disappears after an overnight soak.
Before you replace them, have an engine shop look at your valves - they can spot face the stems if they aren't too badly worn. You'll have to get the seats reground anyway and it can be done as part of that process.
As part of that process, have them check your pistons - a set of liners and new rings will be a lot cheaper than a full rebuild kit if the pistons are still good.
It's also a very good idea to get the mains line honed to ensure they are absolutely straight, or rather, concentric.
Glass beads work extremely well for blasting parts - they come out looking like new but the process won't mar machined surfaces.
I, myself, personally intend to continue being outspoken and opinionated, intolerant of all fanatics, fools and ignoramuses, deeply suspicious of all those who have "found the answer" and on my bad days, downright rude.