Can you advise the location of the 'threaded bolt'
Normally the coil has two 'threaded bolts' one that is connected to +12 volts when the ignition is turned on. The other 'threaded bolt' is on the negative side of the coil and connects via a cable to the distributor, inside the distributor there is a switch (contact breaker) that makes and breaks a circuit and connects to 'ground' ( 0 volts) and passes a current through the coil, which then creates the high voltage on the high tension side of the coil, and the spark at the spark plug
In some cases the wire connections to the coil 'threaded bolt' is by way of a female connector in a rubber boot, that pushes down onto and over the 'threaded bolt'. This type of connection was also sometimes used on fuel pumps, it probably works well when first fitted, but can give connection trouble later in life.
