good day Tham I am from Malaysia too, Kuala Lumpur fellow but staying in PJ

ok so for timing chain I had this experince before so I can comments a bit here.

1. Timing chain will not break but what will happen when timing chain is loose is that it will hit our 4K engine timing chain cover = it does u need to change the timing chain cover

worst situation like my previous engine u can see a hole through it

2. Timing chain my advice is change the whole thing don't change bit by bit but change the whole timing chain plus the gears too.

4K engine there are two types of timing chain

a. single chian - meaning one timing chain

b. dual chain - meaning the timing chain has dual chain in it

hope this helps ur decision