How is this procedure done? Is it the same as the KA24DE where is I'll need valve shims, and if so where do I purchase valve shims? Thanks in advance.

 

the ka24e have hydraulic lifters that don't have shims or latch adjusters. if you need to know because your rattle, then you most likely need to replace them.

i switched to a full synthetic oil and that fixed my noisy lifters

 

That is exactly what is happening.

I am also getting white smoke coming from the exhaust on cold start.

Should I add engine treatment and then change the oil to full synthetic? Thanks in advance.