Marine Exhaust Risers

A riser, sometimes also called an elbow, is a U-shaped component bolted to the exhaust manifold at one end and to the exhaust hose at the other end. This part is basically the point where raw water from the engine cooling system is introduced into the exhaust system for it to reduce the temperature of gases and muffle engine noise. The riser is shaped to ensure a one-way flow of water, preventing it from flowing back into the manifold and entering the motor, where it can do a lot of damage. However, when the riser rusts away and leaks, cooling water will likely find its way into the manifold.

Risers are typically water-jacketed, which means they have a double-walled construction. Hot exhaust gases flow through an internal pipe, while cooling water is “sandwiched” between the walls. These parts are typically manufactured from cast iron. Over time, the inner wall corrodes and develops a leak, letting water into the manifolds. The big issue is that internal damage is not visible and can only be revealed after removing the elbow. That’s why the rule of thumb is to replace it every five years, or sooner if your boat is used in seawater. In our store, you’ll find a high-quality replacement made specifically for your motor.