Ignition Rotor: Testing and Inspection

Fig. 19 Ignition Rotor:

1. Check rotor for any signs of burning, or pitting:
at the tip
at the resistor (between the contact points)
at the center contact.
2. Replace the rotor if any signs are found.
3. Check the resistance between the contacts.
Resistance should be 1000 +/- 400 ohms.
Note: Rotors for conventional (points type) ignition systems are very similar in size and shape to rotors for breakerless ignition systems, and will very often fit in breakerless distributors. A rotor for a conventional ignition system should never be used in a breakerless ignition system, though, because they are not designed to handle the higher voltages and will fail after a short time, possibly damaging the ignition system.