Mercury - Quicksilver Distributor Cap Ignition System Component Reinforced Polymer with Brass Terminals 33765T. Overview. A dependable spark makes all the difference on the water. The Mercury Marine 33765T Quicksilver Distributor Cap keeps your ignition system firing clean and even. Built for Marinized GM 6-cylinder inline MerCruiser engines that use Delco conventional ignition, this cap is tough enough for life in a hot, vibrating, salt-filled engine bay. It's molded from durable reinforced pol