Leaking Head Gasket
I am losing coolant at the rear right area of the head gasket where the water passes between the block and head. When I inspected the 8 head tappet gallery bolts, i found 7 of the eight as I expected; internal torx head and tightened properly. However, the rearmost one, where the leak is, is a threaded stud protruding through a cylindrical device (the size of a small irregular shaped socket) with a wire attached. This discovery was totally unexpected. Should this rearmost bolt be the same as the others? What is this device. Tough to see back there.