What is a seacock valve?

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. Seacocks are left open or are closed depending on the situation.

How do you know if a seacock is open or closed?

All seacocks have a handle that moves 90 degrees from fully open to fully closed, and many have a lever-type handle. When the handle is in line with the outlet, the seacock is open; when it’s perpendicular to the outlet, the seacock is closed.

How do you check through through-hull fittings?

You can check the thru hulls first when scraping the paint from the metal and if it looks golden and not pink, it is in good shape. If the metal is pink, the thru hull fitting should be replaced immediately, since the metal has no strength and is ready to fail.

How do through hulls work?

Thru Hull is a term used to describe a fitting that is attached through the Hull of a Boat. A thru Hull fitting requires a hole to be cut/drilled in the boats Hull for the fitting to pass through. Some examples of thru Hull attachments are a sea-cock and hose and thru Hull transducers.

What is the difference between a seacock and a ball valve?

An industrial-style ball valve has an NPT pipe threaded openings on each end. These accept any number of standard plumbing fittings that have tapered pipe threads. Marine seacocks, on the other hand, have the top end with an NPT (tapered thread) and the flanged end with an NPS straight pipe thread.

What is a sea valve?

: a valve in the bottom or side of a ship communicating with the sea.

How do you get rid of a seacock?

The usual steps involved in removing a seacock are to remove the hose clamps and hose from the tailpiece, then, using the biggest pipe wrench that will fit into the space, unscrew the seacock from the thru-hull.

How tight should a thru-hull fitting be?

Grip the slots in nylon through-hulls with crossed screwdrivers. With the seacock tightened snugly — not too tight — you should have plenty of threads inside the seacock, but the length of the through-hull should not prevent the base of the seacock from tightening against the plywood ring.

Why do boats have through holes?

Limber holes are created in between bulkheads so that one compartment does not fill with water. The limber holes allow water to drain into the lowest part of the bilge so that it can be pumped out by a single bilge pump (or more usually, one electric and one manual pump).

What is the maximum pressure handled by instrument valves?

Usually the max. working pressure for the high-pressure ball valves is 7500 psi and depends on the structure, sizes and sealing materials, the max. working pressure of high-pressure ball valves can be up to 15000 psi.

What is Marelon made of?

Marelon (pronounced “mar – i – lawn”) is a carbon reinforced plastic, or per their web site “Marelon® is a proprietary formulation of polymar [sic] composite compounds using composite reinforced polymer and additives” and Marelon is: U.L. and A.B.Y.C. approved.

What kind of valve should I use on my seacock?

The dog should always face the valve body and with valve open be oriented at 12:00. It should go without saying but when doing below the waterline seacock/sea valve work the parts should be UL Marine labeled. Groco, Spartan, Forespar/Marelon, Apollo/Conbraco, Buck Algonquin and others all sell UL Marine rated seacocks & valves.

What is the UL standard for a seacock?

Typically, UL-listed sea valves include a flange, although it’s not specified in the standard. • 27.6.1 The seacock must be able to withstand “a 500 pound static force applied for 30 seconds to the inboard end the assembly, without the assembly failing to stop the ingress of water.”

What is the ANSI rating for a seacock?

• 27.5.4 “Seacocks shall be designed and constructed to meet ANSI/UL 1121, Marine Through-Hull Fittings and Sea-Valves.” This does not say that just any UL rating or labeling ensures compliance. Valves can be UL listed for countless applications—fuel, LP gas, potable water, and even seawater.

How are tapered cone seacocks machined to prevent leaks?

They are machined in to help retain a marine sealant and thus prevent leaks. You can also see the proper placement of the Jam/Jamb nut and flange nut. I purposely placed the dog washer on backwards to show what not to do. The dog should always face the valve body and with valve open be oriented at 12:00.