Tappet noise

... 修复reconditioning 气门挺杆发响tappet noise (valve knock) 制动器发响noisy brake ...

 collapse of piston skirt

... piston knock(piston slap)活塞裙部挤扁 collapse of piston skirt气门挺杆发响 tappet noise(valve knock)汽门弹簧颤抖 ...