Mercury - Exhaust Riser Kit MerCruiser Exhaust System Cast Iron Component 93320A13. Overview. Anyone who's spent time behind the helm of a MerCruiser-powered boat knows how important a healthy exhaust system is. It's not something you think about often-until it stops working as it should. The Quicksilver 93320A13 Exhaust Riser Kit brings back that quiet confidence you want every time you turn the key. Whether you're easing a tow-sports boat onto plane or cruising a deep-V offshore hull through a