Word forms: (regular plural) rotor arms
(Automotive engineering: Vehicle components, Engine, transmission, and exhaust) The rotor arm is the rotating electrical high-tension contact of the distributor in a spark ignition engine.
⇒ Lift off the distributor cap and take out the rotor arm. ⇒ The rotor arm should be pointing at a notch in the distributor body rim. ⇒ The distributor shaft driven by the engine operates the points and turns the rotor arm.
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