"Roger Long" wrote in message
...
"Jonathan Ganz" wrote

I took a look at the WM site and found an example of a vented loop. Looks
like it might fit, but I'm not sure where yet. It can either be within a
foot or so, or it would have to be at least 3 feet away in the engine
space. I'll have to check it out.


The vent has to be above the discharge and waterline for there to be any
point to it. "within a foot or so" would be OK if you just mean the
lateral distance and not the hose length. The loop should be just as high
in the boat as you can get it, ideally, just under the deck. If your
bilge discharge is high enough above the waterline, you don't really need
a vented loop except to keep surveyors happy. My bilge discharges are
just ahead of the transom and nearly a foot above the water line so I
haven't added vents to the lines which loop even higher under the cockpit
coaming. It's something I'll probably do before going very far off shore
though. If the boat was low in the water due to flooding and the pumps
stopped, a back siphon could be created.

--
Roger Long


Good grief! More vented loop idiocy. STOP THE INSANITY!!!!!!

You vented loop people are confused. Vented loops are a good thing in a
sewage system so your toilet doesn't flood out of the bowl and fill up your
boat. They are a safety device to break any possibility of a siphon on the
intake side of a toilet. The intake side is necessarily placed under the LWL

To put one on a bilge pump is folly - pure folly. In order to keep a bilge
pump from siphoning all one needs do is have the bilge pump discharge above
the LWL of the vessel.

Place the discharge thru-hull about two feet up from the LWL and on the
transom and you have ABSOLUTELY NO NEED for a vented loop. Duh! But, that
idiot drug sponge Ganze will probably install one anyway since he has my
wisdom kill filed. Somebody else please clue the loser in.

Tarnal hell but you Rubes have no business anywhere near the water. Joe
juniors all of you!

Wilbur Hubbard