When do i have to change the timing chain?
Current wisdom says somewhere around 65K miles Lancer, and unless you are noting that you have 89K kilometers on your 1978 Toyota Cressida in your question it appears you are due (65K miles = 104K kilometers). Be sure to run it by your local (and trusted) mechanic but it is certainly time to consider getting the work done.
What year? Chain or belt? Chains have no replacement schedule. Keep on a'drivin'.
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