Keeping the bilge dry

PLUMBING PROJECTS

1. Keeping the Bilge Dry

I like a dry bilge, for several obvious reasons. One of them is to prevent corrosion, an other to avoid mold. It also helps to detect any leaks, of fresh or sea water, quickly (you just have to briefly lift the inspection floorboard in the galley and take a glance down into the bilge).

In normal conditions water should not be entering at more than 3 locations: sea water through the stuffing boxes of the propeller and rudder shafts and rain water through the mast. But in addition to these causes, it is not unusual for unexpected leaks in various locations of the yacht (for instance we have 19 water pumps aboard! - not counting those in the diesel engine).


A big, dry, clean bilge, painted white for visibility. One electric and 2 hand pumps	Water from the mast is directed to the bilge through a hose in two ways, see below

If you click on the left photo, you can see the clear hose coming from the mast. Any water is collected in the plastic bottle and easy to inspect. Not visible in the photo is the ventilation hole, designed so the water wont drain that way, but will keep the inside of the mast dry and increases ventilation around the mast step - there is a good "chimney effect" on sunny days.

The system is not yet perfect, next time I pull out the mast I will install the drain below the mast instead of on the side (on a garden hose type fitting) to make sure that all water is drained. A similar arrangement is planned for the area around the propeller shaft, to collect the drips from both shafts.

I installed the mast step drain a couple of years ago when I discovered that there was serious corrosion. I had to pull out the whole mast step for repair, and it was one of the worst jobs I have ever undertaken - I will never do that again!

Link to the corroded mast step photos

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2. Hoses and Jugs

I use hoses and jugs in several easily inspectable locations, where water may be dripping. Here are some examples:


A leak at the fresh water pump would drain here.	Labeled hoses (This is not in a nuclear plant)

A hose barb integrated in the mast shoe	Rain water from the mast is directed to the bildge, now keeping the mast step dry and uncorroded

More about the mast step in next story.

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3. The Corroded Mast Step

There's probably no easy way to stop rain from entering through the mast. Fortunately it is fresh water so, if you keep the area below the floorboards ventilated, there should be little damage. In the tropics with several rains a day it would be too much trouble to constantly mop out the water.


Only half of it visible, but cleaned	Detail of corrosion

The mast step of Scorpio had apparently been wet for a long time. I had naturally noticed it before, but on the visible starboard side it didn't look too bad, so I regularly just cleaned it, applied Ospho and painted every now and then with a zinc spray.

One year when we pulled out the mast for the replacing of all the wires in the rigging I was able to inspect the port side of the mast step. As you can see on the photo above (right), some areas had corroded quite badly, and I decided to have the whole thing pulled out and repaired.


The keel bolts where glassed in ...	... and had to be exposed

The project turned out to be the hardest job I have ever undertaken on the boat, for several reasons: A) Four of the yacht's seven keel bolts go through the mast step and they were glassed in and had to be uncovered.


We used a car jack to pull it out ...	... but had to cut of pieces of interior first!

B) Part of the joinery of the port settee had to be cut out to allow us to lift out the step. C) The mast step was glued to the bottom, and we had to use a jack to force it free, and D) The bloody thing was very heavy, I would say at least 100 kg!


Mast step is out, keel bolts free.	Pieces of one corroded area

The photos on this page should give a pretty good idea of the magnitude of this project. I would never want to do it again!


Mast step in work shop	Ready to go back!

The lower end of the mast is now fitted with a drain that directs rainwater to a bottle in the bilge (easy to monitor), see previous story. There is also an arrangement for venting the area below the floor boards through the mast.

During our major renovation in 2011-12 we also painted the whole maststep with a two component epoxy paint.


The painted mast step	A hose barb integrated in the mast shoe	Rain water from the mast is directed to the bilge, keeping the mast step dry

More plumming projects: Seacocks and thru-hulls.

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