齿隙调节螺钉 Backlash adjusting screw

间隙螺纹量规 Clearance screw gauge ; Clearance screw thread gauge

径向螺牙隙 radial thread relief

无隙螺纹 no relief thread

气门间隙调整螺钉 valve clearance adjusting screw ; Valve setting screw

气门间隙调整螺母 valve clearance adjusting nut ; TAPPET ADJUST NUT ; Valve setting nut

螺旋缝隙 spiral slit

气门间隙调整螺丝 TAPPET ADJUST SCREW

余隙螺母 [机] clearance nut