If your speedboat hasn’t been performing like you remember, it’s a good idea to take it in for a checkup or, if you are up to the task, start troubleshooting it yourself. There can be a number of reasons your boat isn’t running right. For engines subjected to salt water, one of the main problems can be the marine exhaust manifolds no longer working correctly.
Unfortunately, most boat owners miss this part. They spend countless hours going through their spark plugs, looking at the carburetor, leads, the rotor, etc. But they never stop to notice the thick deposit left on both the oil filler cap and even in the sump.
The issue is that most marine exhaust manifolds are made from cast iron. Unfortunately, cast iron, though strong, durable and dependable, is also very porous and will soak up the salt water it’s exposed to. After a long enough period of time, the metal begins becoming corroded. When corrosion finally eats through the metal, the water used to cool the engine is introduced to the exhaust system.
This is a job for a professional. No amount of cleaning will fix it. Look for a professional that uses sierra marine parts, to ensure you’re getting the best replacements possible. While they may be able to apply a sealant or solder a repair, be prepared for needing new exhaust manifolds at the least.