by Dewey
(Colyer)
Hey Guys, I have a 1975 Mercury 500 50 hp, I have no spark at the Plugs, I was told the switchbox was bad So I bought one used and still same problem? I have searched and I think I should have some kind of power going to switch but not sure how to test? I would like to test the Switchbox (333-3213a3), and if good no how to test Coil, and distributor.