That is because it is not a chain. Mazda uses a timing belt which must be replace at 105,000 miles if not before.
This Mazda engine uses a chain.
The Mazda Mpv 2000 timing chain
The Mazda 6, First and Second Gen, have a timing chain.
chain!
it has a cam chain
Chain ;o)
chain!
It has a timing chain that requires no maintenance.
it has a chain
A 2002 Mazda MPV 3.0 V6 has a timing chain.
The 2.3 litre four cylinder engine in a ( 2002 ) Mazda B2300 has a timing CHAIN
It's a CHAIN