Wet Exhaust Issues

[medmd2010]

my gas crusier (1988 wellcraft - portofino) has a wet exhaust system that draws freshwater. all of a sudden, i have a louder than normal noise along with some vibration along the straight exhuast piping leading to the muffler.

any first thoughts?

thank you.

tim

[Chief Engineer]

First you need to clarify.

Fresh water is the water in the engine that is mixed with antifreeze

Raw water is what comes in from whatever body of water you are in.

Raw water is what cools the exhaust and the freshwater via a heat exchanger.

[medmd2010]

it is on a freshwater lake.

[medmd2010]

it is in a freshwater lake.

[delmarrey]

Got cha, Chief.

Is the exhaust manifold loose? Sometimes raw water cooled systems rust out the bolts.

[Chief Engineer]

Sounds like a "miss or backfire" possibly

[OTIMO]

Good to see a fellow Portofino owner on here! I live on mine in Texas, really love the boat---my dad purchased his new in 87'

I also have a Scarab 38 KV so I am a Wellcraft fan of sorts---


Sorry for the thead drift......