Firstly, what type of tappets does an H22a engine have?....hydraulic? And while on the subject, what tappets does a F22b have also.

Secondly, I've noticed my engine (JDM H22) is making a louder than usual tapping noise on idle after I realised my engine was running low on oil. So I reckon I've caused some engine wear. Since, I have noticed my engine is using more oil, but I cannot see a loss in power or speed, so I don't think the damage is too bad.

What is the likely solution to stop the tapping...adjusting tappets, valves etc?

 

what in the world is a tappet??
as for the increased oil consumption, have a compression check. worst case scenario, your engine starved and and your piston rings nicked the cylinder wall, caausiing excessive oil blow-by