We recently bought a used Sabb Diesel with 8 hp (build early 1970).
The engine is very easy to start and runs like a charm, but there is
an annoying "noice" that is a little bit worrying. The noice seem to
be related with the transmission as it's not heard when the
transmission is disconnected. The sound is not there always and seems
to dissapear (maybe because it's impossible to hear it with more
throttle. Anyone that had similiar experiences with this type of
engine(s)?

Best Regards
Niclas