I actually found a lot more from one of my searches.. is the later 2017-2020 3 cylinder kapper engine the same as the one on this thread.. anyone know ? I now have a workshop manual for the above.. 😈Well the fact that there is a spec does not mean that there is an adjustment.any more than there is an adjustment for Journal Outer Diameter. I would be very surprised if they were not hydraulic. Even in the days of rockers and adjusters there was not any requirement to adjust tappets at any particular mileage - you could hear when they needed doing. Later came directly operated valves (no rocker) where the clearances were set with shims but rarely needed doing unless valves were replaced or head removed. Why not whip the cam cover off and see if there is any adjustment possible - I'll expect that there is none.