Run your search on Detroit Diesel 6V92 for lots of info.  It
is a V6 diesel engine manufactured by GM with a displacement
of 92 cubic inches per cylinder.  It is supercharged and
possibly has a bypass turbo depending on config.  They were
so-so as far as reliaility compared to other HD diesel
engines but were popular in the bus, construction and marine
applications. They were known to use and slobber oil and
fuel from the exhaust and met their demise because of
emissions regs here in the states.  They need regular
maintenance to keep them operating properly w/o heavy smoke.
Even though the later of the series was considered to be
"fuel efficient" they are no match for the far superior
Series 60 engines that replaced them.  Here in the states,
it is still easy to find service for them.  You may want to
check the engine s/n to see if it was one of the early ones
with the old crosshead piston design.  If it is, don't even
look back as you run away.

If you look for used coaches, you will find that the ones
with a Series 60 or other more modern engine design are
worth about twice the cash with only a year or so difference
in age.  If you can find and afford a bit later unit with a
Series 60 engine, you will be way ahead of the game in the
long run especially if you intend to put many miles on it.
If I were looking at it, I would not want it unless it could
be bought cheap enough to afford to repower it with a Series
60 assumming it could be repowered that way.  Contact with
the manufacturer may provide some info on that.

Lugnut