Right what you need to do is take off you rhead gasket where the pistons are and adjust the tappets as they have obviously losened. If you have a fila gauge then it will be easy to do. All you need is a socket set, screwdriver and spanners. for your polo i would then you need a 0.30mm clearence on the exhuast valves adn with the inlets valves i should think 0.20 clearence will do it. If this isnt the prob then adjust them anyway. Will be good so you bearings dont get crushed. Echo.Josh X-x-X