How long do marine exhaust manifolds last?

six to eight years
Most experts suggest that a manifold will have a life expectancy of six to eight years. However, heavy use in saltwater can see this drop to as low as three years, while lightly used freshwater boats can get up to 20 years out of a manifold.

Are exhaust manifolds aluminum?

Considering the exhaust manifold needs to be corrosion resistant, the common materials are aluminum and stainless steel in the market.

Why do marine engines have water-cooled exhaust manifolds?

A water cooled boat exhaust muffles engine noise. By injecting cooling water into the exhaust pipe, the noise quietens. The water is transported from the water-cooled inboard engines and then pushed out of the exhaust pipe by the exhaust.

How long do MerCruiser risers last?

Mercruiser, for example, has a wonderful reputation for risers that sometimes don’t last a year. On average, in saltwater use, good risers last about 4-5 years. At 4 years, you should start worrying about them.

How do you clean a marine exhaust manifold?

Clean them with a scrub brush With the exhaust manifold removed, you will be able to start cleaning it. Grab yourself a scrub brush and then apply some type of lacquer thinner to it. Scrub the manifold vigorously so that you can remove built-up debris and any type of rust that has started to form.

Why does water come out of the exhaust on a boat?

Re: Is it normal to have water come out your exhaust? It’s normal for cooling water to also exit through the exhaust. It’s part of the cooling system (in addition to the pee stream). And when you aren’t moving, the exhaust might bubble out from the lower unit because it also exits out through the prop while underway.

Does boat exhaust pollute water?

Two stroke motors can emit 25-30% of their unburned gas and oil mixture into the water. In contrast, four-stroke motors emit 97% less air and water pollution than old two-stroke motors. This pollution can affect the pH and dissolved oxygen in the lake, which can influence the type and abundance of fish and wildlife.

How often should Mercruiser manifolds be replaced?

The stainless steel manifolds often come with anodes and a large sticker that states “replace every 3 months”.

What kind of exhaust manifold does marine power use?

Marine Power high performance semi-tuned aluminum exhaust manifold. Fits 5.0L/305ci and 5.7L/350ci engines. Can be used with fresh water or raw water cooling systems. Manifold comes unpainted ready for primer and paint. Dry joint Mercruiser style iron center-rise exhaust manifold.

What is an individual primary exhaust manifold?

These manifolds have individual primaries for more torque and horsepower over your stock center rise or log style exhaust manifolds. This is a great choice as an upgrade from log style manifolds.

What size exhaust hose for this manifolds?

These manifolds have a steep down slope originally designed for jet boat applications. Riser fits 3-1/2″ exhaust hose. From center of exhaust port to end of riser is 13-1/2″

What does a MerCruiser exhaust manifold and riser kit include?

New exhaust manifold and riser kit for MerCruiser small block marine gas engines with dry-joint style exhaust (2004 and newer, 5.0L, 5.7L, 6.2L) Does not replace older manifolds, log style manifolds, or 14 degree down-angle risers. Comes with gaskets and hardware. Kit includes parts to configured for both Raw and Fresh Water Cooling Systems.