Although Ford has changed the location of the starter over the years, the manufacturer really hasn't changed much to the design and functionality. The starter motor bolts onto the side of the transmission housing and uses a starter solenoid to kick the small gear inside the starter for the transmission. If your Ford starter won't engage, you need to troubleshoot the starter to determine if it is the battery, ignition, starter motor or starter solenoid that's causing the problem.
Place the red lead of a multimeter onto the positive battery terminal. Place the black lead of the multimeter onto the negative battery terminal then set the multimeter to 20 DC. Inspect the meter for the voltage output. If the reading is less than 12 volts, charge the battery and attempt to start the vehicle again. If the starter still does not kick in, move on to the next step.
Turn on the headlights of your Ford then turn the key in the ignition. If the headlights dim, the ignition switch is sending power to the starter. In this case, move to the next step. If the lights do not dim, the ignition switch is likely defective.
Locate the starter solenoid under the Ford. The solenoid bolts to the starter motor, and the starter motor bolts to the side of the transmission housing.
Place a screwdriver across the two metal contacts on the back of the starter solenoid. This will short out the solenoid and create a connection between the starter motor and the solenoid. Have an assistant turn the key in the ignition. The Ford's engine will not start. However, the starter motor should turn on and begin to hum. If it does, the solenoid is defective and cannot produce enough power to kick in the starter gear. If the starter motor does not turn on or it runs very rough, the starter motor is defective and does not produce enough power to turn the starter gear.