Hi there I have a 1978 triumph t140v , are the 2 marks on the alternator rotor that are 180 deg apart indicating TDC or 38 Deg BTDC.for each cylinder. Cheers Dave
Use the line next to the Lucas in casting and turn engine anti clockwise (primary side) past the pointer and line it up with the bottom right hand hole (one of the three cover screw holes) this is TDC, the pointer is used for strobing or static BTDC setting 38 DEG. Sorry i just realised the T140 does not have the bigger 3 screw cover and only had a small plug at the top for strobe timing, with either type the line on the rotor shows 38 DEG BTDC with the pointer.