Mazda Trucks 1972-1986 Repair Guide
The distributor cap on all engines is held on by two screws. Remove the screws and lift the cap straight up with the wires still attached. Inspect the cap for cracks, carbon tracking and worn contacts. Replace it, if necessary, transferring the wires one at a time to avoid miswiring.
On 1979 models, pull the rotor straight up to remove it. On 1980-86 models, the rotor is held in place by two screws. Use a magnetic screwdriver to remove them and lift off the rotor. Replace the rotor if it appears worn, burned or pitted.
Inspect the wires for cracks or brittleness. Replace them, one at a time, if they appear at all suspect. Avoid bending the wires sharply, or kinking them, as the carbon cores are subject to such damage.