Thru Hulls and Valves

One of my Spring of 2011 projects was to replace the ticking time bombs ( Yellow Bronze gate valves ) on Wind Dragons thru hulls.  A BIG thank you has to go out to MaineSail, on the SailBoatOwners forum, for his How-To’s [Compass Marine].  There were a total of 5 below water and 1 above water thru hulls that needed work.
Thru Hulls removed:

  1. Galley sink outlet 1-1/2″
  2. Raw water intake 3/4″
  3. Depth sounder 1-1/2″
  4. Speed sensor 1-1/2″
  5. Head sink 1″

Thru Hull repaired:

  1. Black Water outlet 1-1/2″

Thru Hulls added:

  1. Raw Water intake 1″
  2. Depth, Speed, Temp transponder 1-1/2″
I am eliminating the sink drains in favor of a Gray Water system that discharges out the Black Water outlet.  I will be using the existing manual pump located in the starboard lazarette that was for the original Black Water system.I am also eliminating the two transponder holes in favor of one “Correctly” located one (forward and more center then they were)

I am also eliminating the current Raw Water hole in order to locate the valve in a more accessible location.

Please see the “Fixing Unwanted Holes” project page for details on that process.

Please see the “Gray Water System” page for thoughts and details of that project.

Please see the “New Depth, Speed, Temp” page for thoughts and details of that project.

origSinkGateValve1 This is an image of Galley Sink thru hull valve,  located under the port side salon seat, that a previous owner installed.  It is a 1-1/2″ gate valve made of, I believe Yellow Brass, like you will find in your Home improvement or Harbor Freight type of store.  Yellow brass is 33% Zinc and the Zinc gets eaten away over time because of electrical currents created by different metals in salt water.After reading about this issue on the boat owners forums I sealed off the compartment this valve was located in.  Any pressure or impact on this valve would have very bad results!  The image you see is the result of ONE whack with a normal claw hammer.

This thru hull was the deepest and at 1-1/2″ diameter, posed the largest risk of water intrusion.  These facts caused me to figure out a “better” way of dealing with the galley sink gray water and allowed me to eliminate the need for this thru hull and valve.  This will be discussed in the “Gray Water” project post.

wasteThruHullHole This image shows the hole where the original “Black Water” thru hull and valve were located.  The location of this is in the starboard lazarette towards the stern.  This hole was kept where is but redone the way outlined by MaineSail in the link above.The white square area is where the original plywood backer board was attached to the hull with some type of adhesive sealent.  The thru hull and gate valve were the same as above but not in quite as bad of shape.  Still, there was no hope of seperating the two so my Saws-all was used to remove.  It was a matter of cutting the valve off the thru hull and then cutting two slots (about 1/2″ apart) down the tube, through the nut.  Then using my hammer and pliers, bending the 1/2″ peice back and forth until it broke off. then used the hammer to tap the remaining part of the nut sideways untill it broke off.  Then with just the thru hull tube left, hammered it out through the bottom.Using my side grinder with a sanding pad, I cleaned up the area around the hole.
1-1:2FlangedAdapt This image shows the 1/2″ fiberglass backer plate that has been attached to the hull with West System epoxy mixed with bonding filler.  The white stuff is LifeCaulk.  The bronze flanged adapter is fastened with 3 stainless bolts through the hull and backer plate.
newWasteTHullOutside This image is the outside of the assembly shown above.  You can see the thru hull, 3 countersunk stainless bolts and LifeCaulk.
newWasteTHullAssembly This image shows the new bronze ball valve and pipe nipple.  All compleate and ready for the hose to be attached.
1inBackerPlate Here you see the new Raw Water inlet location with the 1/2″ fiberglass backer plate in place with the bolts and thru hull hole.The original Raw Water inlet was 3/4″ but I decided to make the new one 1″ to accomadate using it for the future AC system water intake.

The new location is under the rear quarter birth as you see in the images below.

newRawWaterInletLocation2 Here you can see the new Bronze ball valve and pipe nipple through the new access port.
newRawWaterInletLocation1 Here is another view of the new Raw Water inlet location.  The engine is to the left and you are looking aft into the rear quarter birth area.
newInletAndStrainer Here you can see the new Raw Water inlet valve and Strainer in place and connected.
newRawWaterInletOutside Here you can see the outside part of the new Raw Water intake