Advancer maybe?

By zachsnacks: .... Back to advancer?

I would clean, check & lubricate the timing advancer. Separate the rotor from the body & fill the groove with grease (if yours has the groove). After reassembly & lubrication, twist & release the rotor >> it should snap back. Check the springs to make sure they aren't stretched or damaged. There may be other stuff to check. & you could check it with a timing light. Get an engine cover gasket beforehand.

I've been making plugs for the 550 carbs. Delrin, aka acetal works really well. I've had some samples soaking in gasoline/alcohol for 2 years with no discoloration or expansion. McMaster -Carr has a large selection of white acetal rod. Its really easy to work with too.