All Mits engines of interest to us (4G63, 4G93) have hydraulic tappets and a reet bugger they are too!
Although according to accepted wisdom they don't need adjusted, they racket they can sometimes produce makes you wish you could. A good semi or fully-synthetic oil of 10w50 grade or similar (most folks have problems with the 'thinner' 0w40 grades) and a decent filter with a good anti-drain flap can cure them but it is a bit of a black art finding a good filter.