It has a cam chain not a belt, as for changing it, I can't seem to find that
information in the manual but I expect someone else on the NG will have the
answer. As a matter of interest the chain on my 1600 Primera is still the
original and has done 108.000+ miles and there's not a rattle to be heard.

Trevor Smith

My '94 Primera cam chain had 158,000m on it with no rattles.  They are
rumoured to last 250,000m minimum and no one ever bothers to change them.
Very early ones (90-93) had problems sometimes with the tensioner but that's
easy to change.