21
May
From a recent project addressing many of the issues with poor quality seacocks I am please to endorse a new type of Seacock which I have been involved in the development of. The thru-hull is fastened to the mounting pad and hull by a large nut on the inside of the boat.
This arrangement a ball valve mated to a through hull fitting often passes for a seacock however its anything but.
What is a seacock on a boat. A seacock is a valve on the hull of a boat or a ship permitting water to flow into the vessel such as for cooling an engine or for a salt water faucet. Or out of the boat such as for a sink drain or a toilet. Seacocks are often a Kingston valve.
What is a seacock. Its a shutoff valve sometimes a simple ball valve with a handle for shutting off a thru-hull fitting. The valve is normally located on top of the thru-hull fitting so it can be shut off incase the hose breaks or maintenance on the system is being done.
Another type often used as a seacock is a ball valve threaded onto the thru-hull. The thru-hull is fastened to the mounting pad and hull by a large nut on the inside of the boat. The ball valve is then threaded onto the end of the thru-hull and the hose bard is screwed onto the other end of the valve.
By Tom Burden Last updated. A proper seacock is more than just a mounting flange with holes for bolting it down. It contains specially arranged internal threads top and bottom which is why an ordinary ball valve or gate valve should not be used in a hole in the bottom of your boat.
The lowly seacock is all that stands between the sea and your boat Photo by Graham Snook Clearly with any device that penetrates the hull of a yacht the choice of materials design and method of installation is paramount to the safety and integrity of the vessel. That seacock is also hidden under something possibly nowhere near the intake seacock. If it only flushes into a holding tank–if the boat even has a holding tank–there should be a deck pumpout fitting somewhere on the side deck.
It looks like the water and. A seacock is a heavy bronze valve that allows you to close a thruhull on a boat. A thruhull is exactly what it sounds like a hole thru the hull.
Thruhulls can be most importantly classified as above or below the waterline. If a hose connected to a below the waterline thruhull fails in the absence of a workable seacock water will enter and in. New boats built to NMMA certification standards have UL-Listed seacocks that are installed correctly with a backing plate against the hull to distribute the stress.
When checking the seacocks be sure they are UL-Listed for marine use. Sometimes theres a plate with the UL seal but sometimes it is on the handle. There are many different types of seacock assemblies available we always recommend using the best quality materials available as any corrosion in this area could result in a major problem and could cause sinking of the boat.
Make sure the materials match and are suitable for your hull type. Yachting Monthly is campaigning for tougher rules on seacocks which currently only have to last five years according to a European directive. Our whistleblower surveyor Paul Stevens 58 a founding member of British Marine Surveyors Europe blew the lid on the directive after finding a worrying number of yachts fitted with brass seacocks designed.
Most seacocks today are of the ball-valve type. From fully open to fully closed is one-quarter turn. The handle opens the valve when its in alignment with the direction of the flow and closes the valve if its positioned across the flow.
Seacocks and fittings found when surveying yachtsmotor boats. From a recent project addressing many of the issues with poor quality seacocks I am please to endorse a new type of Seacock which I have been involved in the development of. Make no mistake about it a failure of a seacock or related raw water plumbing component could lead to catastrophic flooding and the loss of your vessel dockside or underway attended or unattended.
This arrangement a ball valve mated to a through hull fitting often passes for a seacock however its anything but. 2744 Seacock A type of valve used to control intake or discharge of water through the hull. It is operated by a lever type handle usually operating through a 90 arc giving a clear indication of whether it is open or shut and is typically of the two following types.
Proper Seacock A tapered cone or ball valve type valve with a handle that rotates only 90 degrees that also has an integral flange. Whether this is on or off the boat it is still called a seacock as that is its only designed purpose. Ball Valve This is still called a ball valve until you install it on the top of a flanged adapter or a thru.
The guidelines set forth in the American Boat Yacht Councils Standards and Technical Information Reports for Small Craft Standard H-27 Through-Hull Fittings and Drain Plugs revised in July 2008 make it clear that seacock installations must be robust and durable. It specifies that each penetration below the waterline should be fitted. A seacock is simply a valve with a built in flange into which a thru-hullskin fitting fitting is inserted.
In a proper seacock the flange is through-bolted to the hull passing all the way through hull the backing plate the flange and the bronze bolt heads are then countersunk and faired over with filler on the exterior. The seacock and the through-hull fitting must always be the same material. Never attempt to install a nylon seacock on a bronze through-hull nor a bronze seacock on a nylon through-hull.
Tighten the two parts together. Most boatyards have a special step-wrench. The importance of Boat Seacock Valves their Accessibility.
A seacock is a valve on the hull of a boat or a ship permitting water to flow into the vessel such as for cooling an engine or for a salt water faucet. Or out of the boat such as for a sink drain or a toilet. Seacocks are left open or are closed depending on the situation.
Seacocks feeding into or out of a closed. Essentially water is pumped into the boat from the sea through a hull fitting called a seacock. The water is pumped into the bowl prior to use and immediately after use to create a wet toilet bowl setting that we are accustomed to in traditional land based toilets.
The above process is faster and easier with two people one working the seacock from inside the boat and the other outside the boat painting the balls. If you have the old fashioned seacocks with the tapered cylinders you should. Installing seacock in aluminium Having converted a 30 ft alum.
Ships lifeboat into a motorsailer be very aware of the galvanic scale when working with aluminium. Stated high quality non metalic thru hulls are excellent and just as strong as those made from metals and on my project passed the marine survey no problems.