You usually don’t replace a timing chain until there is a problem. The chain is running through an oil bath and gets well lubricated and lasts the life of the motor in most cases. A timing chain that is going bad often makes noise before it lets go completely.
When a motor is torn down and rebuilt that is a good time to replace the timing chain while the motor is apart. Most motors with timing chains are non interference motors, meaning a broken chain doesn’t damage the valves and pistons. I’m not sure if your particular motor is an interference motor or not.