comments:
NightKnown405 posted on r/askmechanics6d
You need a tool like an ST-125 HEI Ignition tester to see if you are getting spark all the way out to the spark plugs. Amazon.com: OTC 6589 Electronic Ignition Spark Tester white : Automotive If that fires at the spark plug end of the wire, then the rotor is fine. Unless the rotor is obviously damaged you can't really tell just by looking, except for maybe pulling it off of the distributor shaft and seeing a burn mark through it.