I have never replaced those bolts (unless they came with the shortblock) and
never had a problem.
'Course I am a woman and therefore not prone to breaking bolts!

Entity Dan Snow spoke thus:

> Let's just say hypothetically I know this dumb idiot who, in the course of
> rebuilding his diesel engine, neglected to notice that one should always
> replace the bolts that attach the flywheel to the crankshaft.

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