Routing Hoses for Vents and Drains

After the new thru hulls are installed and the sealant is cured then it is a good time to run the hoses for the rear locker sacs and also the drain lines.  I decided to install those lines at this point because the vents for the locker sacs will use the existing 3/4" stock thru hulls that were originally used for the drain hoses coming from each hard tank.  The thru hulls are very difficult to reach so it makes it a bit easier if you connect the vent hoses for the locker sacs first since they would be obstructed by the drain lines if you were to attach those first.

So begin with the vents for each locker sac.  Many people are now running their vents to the opposite side of the boat.  So the port locker vent goes to the starboard thru hull and the starboard locker vent goes to the port thru hull.  This is done so that water is not lost through the vent when the boat is fully weighted down on one side.  When the boat becomes weighted, the same-side vent actually becomes lower than the top of the sac and gravity along with the rocking of the boat will cause water to seek its way out through the vent.  I figured this was a good idea so that is what I did as well.

I installed check valves in each vent line as close to the thru hull as I could while still allowing them to be accessed.  I used 3/4" check valves supplied by wakemakers which are serviceable so I wanted to make sure they were easy to get to in the future.  The check valves will allow water to be vented overboard but will close when the sac is being emptied.  That allows the pump to suck all the water out of the bag without drawing in air.

Here is a picture of the vent line coming from the bow sac and out the port side of the boat.  This view is from inside the observers seat storage compartment (under the glove box area).

As you can see, I routed the vent hose for the bow sac over the the divider and then down under the bow seats.  There's a small opening at the top of the divider to route the hose.  I recommend trying to route all your vent hoses as high as possible to help prevent water from escaping when the boat is leaning.  You can also see the 3/4" check valve in this picture.  Try to keep the hose between the check valve and the side thru hull sloped downward so that water will not become trapped in the short piece of hose.  This will lower the chances of trapped water freezing in the hose during winter months.

After I had the rear vent lines ran then I started on routing the drain hoses.  The drain hoses run from just behind each pump.  Remember that I had installed check valves on the supply lines so that water would be diverted overboard when the pumps are emptying.  Here is a picture of the port pump and notice the drain hose which is attached to a street elbow threaded into a 1" tee.  My drain hose and fittings are all 1".

Remember to also install a 1" check valve close to where the drain hose is attached near the pump as shown in the above picture.  This is needed so that the pump will not draw in air from the drain hose when it is in the process of filling the sacs. You want to make sure the pump is only sucking water and no air when filling.  The check valve on the drain hose will allow water to be drained but will not allow air to be sucked back in.  I originally had the check valves installed closer to the side thru hull but I found after doing a water test that the pumps were sucking in air through the check valves.  I called wakemakers and they did not have any good solution.  They told me that these check valves were chosen by them because they did not have a history of this type of issue like other brands have had.  The only thing we could think of to try was to install the check valves closer to the pump in hopes that there would be enough suction to close the flapper and make a tight seal.  A water test with the valves closer to the pump showed that it did help a bit.  They still sucked some air during the initial test but I found that they closed up once some water was sent out the drain hose.  Having the check valve lower in the boat allowed the remaining water in the drain hose to help keep the flapper closed when the pumps were filling.  

As mentioned in a previous post, I used two 1" chrome thru hulls for my drains.  I purchased them from wakemakers.  When I received the 1" thru hulls I realized that the barbed end is technically meant for a 1 1/8" hose.  The website isn't clear on that.  The reason I bring that up is because the slightly larger barb makes it extremely difficult to get the 1" drain hose over the barb in that tight of a space.  I tried to heat up the drain hose quite a bit to get it to slide over the barb but it was not working.  I either made the hose too soft to work with or I didn't heat it up enough in other attempts.  I struggled with it for a while.  The hose I chose to use does not stretch very much.  Finally! the lightbulb came on in my head.  My tsunami pump uses a 1 1/8" hose and it stretches very easily.  So I sacraficed a few inches off my Tsunami pump's hose and it worked like a charm.  My tsunami pump won't miss it because it already had a very long hose on it.  I put a 1" elbow onto my 1" drain hose and then attached the short piece of 1 1/8" hose to the elbow and then easily put it over the barb on the thru hull.  Clamped everything real tight and did the same thing for the other drain hose. 

I was glad when I was finished attaching the vents and drains to the thru hulls.  It is not easy to get your hands back in there and still be able to see what you are doing.