Is it okay for a 230,000km engine to start using 20w-50 oil? I notice that after use 20w-50 the engine more torque, smoother. But there's tappet noise after cold start or leaving the car off for about 2 -3 hrs, start again will have tappet noise for about 10-15 secs

I concluded that 20w-50 made it smoother because the clearances in the engine has increased after 230k-km and the thicker oil can seal up this clearances instead of the recommended 10-30.

Tappet noise during start is cause the oil is thick, need some time to reach the head?

Sifus, is my conclusion correct?