Bruce wrote in
:

On Sun, 22 Jul 2007 15:06:13 -0400, Wayne.B
wrote:

On Fri, 20 Jul 2007 15:59:50 -0500, Geoff Schultz
wrote:

My plan is to replace the existing mixing elbow with a dry stack.
Basically I'll cut off the big round can and replace it with a 10"
high stainless tube U that will have the raw water entering 1/2 down
the side that connects to the muffler. I'll wrap the whole thing in
insulation to reduce the burn potential and heat.

Does this sound like a reasonable solution to this problem?

Perhaps, but take note of Bruce's comments.

What you describe is not truly a dry stack but more closely resembles
a "riser" in power boat language. A true dry stack has no water entry
at all and usually exits vertically through the deck like a lobster
boat. Many commercial fisherman and some long range trawlers use dry
stacks and keel coolers to totally eliminate raw water cooling and
exhaust issues.

An added comment. According to some of the blokes standing around on
the jetty you are not supposed to use stainless to make exhaust parts.
NOT NEVER!

I have built boat exhaust systems out of both "black iron" and
stainless and can't really see much difference. Do use stainless pipe,
not tubing, as the pipe is much thicker and will last longer. My
present stainless elbow, on a 40 hp, engine, has passed ten years and
is still going strong.

Bruce in Bangkok
(brucepaigeatgmaildotcom)

I was planning on using schedule 40 SS pipe. Thanks for the feedback.

-- Geoff