What does it mean by Tappet ROSAK?

[CcL]

my mom's car with a boxer engine cannot start and engine sounded really bad when try to start it... sent to a mech and the fellow say tappet spoil.

just wanna know how can tappet spoil? i tried googling it also no definite answer. tappet for this engine also damn hard to find so is there anywhere can custom make it?

sifus help me plz.....

 

[yuh_woei]

Connection between rocker arm and the Valve. look like a coin if i am not wrong,Boxer engine not really sure but you can ask all the Sifu at car mod section.They might give you some info.

Cheers