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Jeff Morris
 
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Default Siphons, anti-siphons & wet exhausts

"JAXAshby" wrote in message
...
jeffies, jeffies, jeffies why is it
sooooooooooooooooooooooooooooooooooooooooooooooooo ooooo difficult for you to
understand English, as the language is used. let's take a look at the term

you
can't seem to understand, to wit:

a siphon break is
"recommended in applications where the exhaust manifold may be below the
waterline at any angle of heel."


take a look at that, jeffies. read it again. and again. and again, until

you
understand that "exhaust manifold" in this case means **the point of the
exhaust manifold open to ambient air pressure**.
In other words, the water injection point.


I keep reading it and your words are not there. Engineering and fantasy are not
the same thing, jaxie. The ABYC standards are complete with pictures labeling
the "manifold" and other exhaust components. If they meant that a siphon break
was need if the injection point was below the waterline, they would have said
so.



jeffies, the exhaust manifold has just two openings in it. the opening to the
engine valves and the opening to pipe leading to the water lift muffler. I
know this may be difficult for you to understand, jeffies, but every last

piece
of the exhaust manifold is metal, the pieces bolted together not only water
tight but **air** tight. jeffies, water can not go through the metal walls of
the exhaust manifold. It can't. water can only get into the exhaust system
through the water injection point. That's only. Only place.

Therefore, **the part of the exhaust manifold allows water into the system

MUST
be above the water line** (ignore special cases requiring special care that
might be used in racing boats and/or military applications).


If this was so important, why is it never mentioned in the ABYC standards? Why
can't you find a single site that backs you up? Why do the standards give
specific instructions for when the manifold is under the waterline, after they
describe how risers are connected to the manifold?

Obviously, the experts do not agree with you. The wording is unambiguous and
clear.



jeffies, you are arguing something you don't understand. It is the water
induction part of the manifold


The manifold is the manifold. Redefining the terms to suit your argument
doesn't change the law. The ABYC standards even describe the construction of
the pipe that connects the manifold to the injection point: "The section of
the exhaust system extending from the engine manifold to the point of water
injection shall be constructed the same as a dry exhaust system."


that has to be above the water line, not the
engine valve part.


Sorry jax, you seem to be all alone in this.

You still haven't explained how all those boats that have the engine well below
the waterline magically have the manifolds above the waterline, at all angles of
heel. You seem to claim the designers build their boat around the concept that
the engine must be as high as possible. The truth is the opposite: the engine
is mounted as low as possible, mainly to keep weight low, but also to minimize
the shaft angle, and to keep the engine out of the saloon. Maybe this is why
the standards never once mention that the injection point must be above the
waterline, but they do say that a siphon break is needed if the manifold is
below the waterline.