Sierra Marine Exhaust Hose & Mufflers

Marine wet exhaust runs hot and handles both gases and cooling water, so the hose and components have to be built for the job. Sierra makes the exhaust hose, mufflers, tubing, and fittings to keep a wet exhaust system tight and safe. This collection covers softwall and wire-reinforced exhaust hose, mufflers, heater hose, and hose menders. Buying right comes down to matching the hose type and inside diameter to your engine and routing.

How wet exhaust works

Most inboard and sterndrive engines mix cooling water into the exhaust to quiet and cool it, then push the mix overboard. The hose carries hot gas and water, so it must be marine exhaust rated, not heater or fuel hose. Using the wrong hose risks a burn-through and water finding its way back into the engine, which is an expensive failure. Proper exhaust hose also resists oil and fuel vapors that are common in engine rooms.

Softwall or wire-reinforced

Straight runs use softwall exhaust hose, which is simpler and less expensive. Anywhere the hose bends, like over a riser or around a tight corner, use wire-reinforced hardwall hose so it cannot collapse and choke the flow. A collapsed hose backs water up and can flood a cylinder, so reinforce the bends. Always check the bend radius rating when planning the route.

Size by inside diameter

Exhaust hose is sized by inside diameter to match your engine outlet and risers. Measure the existing hose ID or check the engine spec, and match it exactly. Stepping down chokes the exhaust and stepping up will not seal on the fittings, so get the ID right and double-clamp every connection with marine clamps. Keep spare clamps on board for quick repairs.

Mufflers and water-lift

A muffler or water-lift quiets the exhaust and, in many installs, lifts water clear of the engine so it cannot siphon back. Match the muffler inlet and outlet to your hose size and the layout of your exhaust run. Replace a cracked or waterlogged muffler before it lets water reach the engine. Some water-lift designs include a drain plug for winterizing.

Replace aged hose on schedule

Heat, salt, and time harden exhaust hose until it cracks. If the hose is stiff, charred, or weeping at the clamps, replace it. A failed exhaust hose is a flooding and carbon monoxide risk, so do not wait it out. Inspect the full run at least once each season and log the replacement date for future reference.

Not sure what your exhaust needs? Tell our techs your engine and hose size, and we will match the exhaust hose, muffler, clamps, and fittings so the system runs tight and keeps water where it belongs. We also carry the stainless steel clamps and silicone sealant that complete a professional install.