This post is also available in: Italiano (Italian)

“Everything on board may break…….and it’s likely that – sooner or later – it will”

Who among us does not hardly withhold a talismanic gesture when hearing this old saying?

Of course this is not the quintessence of confidence, however, in a pragmatic approach, being aware that something may go wrong, helps to prevent UNfortunate events mainly through the acquisition of information and tips to remedy possible trouble without risking the life and the boat.

Water on board: the topic of today has clearly nothing to do with drinks stocked on board! Instead it is about the presence of water in the bilge. This forces to act rapidly, yet calmly and safely to avoid that this unfortunate event may turn into a serious trouble.

Taking for granted that the reason why there is water in the bilge is unknown as it is not due to a sudden and unexpected cause such as striking a half-submerged object or a collision, the first thing to do is to determine the nature and the origin of the water.

Firstly – although it may appear trivial – stop everything and be as silent as you can while you try to hear the noise of the water flowing in the boat.

Immediately after that, you have to taste the water. This is surely quite disgusting (actually a bilge is not the cleanest place in the world!) but it allows you to know if it is salt or fresh water and focus on one of these two possibilities.

If it is fresh water, the source of the leak is inside the boat and – generally speaking –  it will not be very serious. On the contrary, a salt water infiltration inside the boat can be caused by an ongoing damage, even serious, which has to be dealt with the utmost urgency and attention.

Fresh water

Let’s start from the most favourable scenario: in the bilge there is fresh water, or rather, we are reasonably confident it is. In fact, salt water residues, traces of fuel, lubricants and dirt in the bilge could mislead the “tasting” of the water in the bilge. Yes, I know, we all are very careful to keep our bilge clean and dry, but, let’s say that it might happen.

Should this be the case, the presence of water may have something to do with on-board services or more “structural” factors. Starting from the last ones, first of all make sure no companionway, hatch or porthole has been left open, then check all gaskets to verify they are not dry or damaged.

The leak may be also due to through-shaft perspiration, which, especially in winter, usually undergoes significant changes in temperature. Condensate drips inside and outside the extruded profile and deposits in the bilge.

Also condensation from the fridge or from the air conditioning system may be the cause of water in the bilge. Don’t be upset. Stop the boat as soon as possible to pinpoint the leak or at least to reduce it temporarily.

Another common cause is a failure or breakdown of the hydraulic system. The first thing to check is the water tank: this is no doubt the most serious and annoying failure as, in most cases, the tank has to be replaced.

On-board water tanks are made of stainless steel or PVC. SS tanks may be damaged along the weld, inlet or outlet couplings or vents. Pass your hand carefully over the tank surface, along the welds and on couplings and vents to make sure there are no anomalies.

Close all the points of water consumptions and then check if the fresh water pump first stops working and then works jerkily. This shows that the problem is in the hydraulic system. In fact the pump stops once the system is under pressure. Any leak somewhere makes lower the pressure and the fresh water pump will start again to restore it. The frequency of these cycles allows to infer the amount of water wasted through the leak.

Identifying a leak in the system is by no means easy, as it might be anywhere. If the hydraulic system is old and clamps are made of steel, check them carefully, then install new clamps before removing the old ones.

If, despite all your efforts, the leak in the system has not been identified, yet, try to accurately dry the bilge upwards towards the gunnels. Then divide the boat in areas and pour little flour on the bilge one area at a time, 20 cm or more up to the round bilged hull. Now the water leak will be easily visible on the flour.

Salt water

But if the water you taste in the bilge is salt or brackish, the problem is certainly more serious as the cause is obviously exogenous. In simple terms, there is a seawater infiltration that has to be identified and repaired as soon as possible.

Seawater may enter a sailboat from several, but luckily not too many, openings, which can be checked fairly easily and quickly.

They are: the rudder trunk, the shaft stuffing box, electronics fairleads and sanitary facilities (toilets and kitchen).

But let’s go in order: it is quite easy to check the rudder trunk. Just open the aft peak and verify if the bilge is dry. If you check for an infiltration after a close hauled run, this, if present, should be quite visible.

If an infiltration has been identified, check the bushes outlet and the access point of the rudder stock and of the fiberglass parts that support it. 

Very often seawater filters through the shaft stuffing box. Boats provided with a shaft line propeller, especially if not brand new, may still have a packing stuffing box. Check for a small infiltration after engine off or idle: if water enters even at still shaft, the stuffing box shall be adjusted and revised.

Check also echosounder and Log terminals as the exit bores of these devices may very often turn into access to seawater.

Let’s move to sanitary facilities: WC and kitchen sea-cocks can easily let water enter if they are left open during a close hauled run. It goes without saying that they should always be closed before starting sailing especially under strong breeze and rough sea conditions.

Finally, the most serious event: an infiltration through the bulb or a leak somewhere in the quick-work.

The first check is the easiest to be performed: you just have to raise the sole where stud bolts and relative counter-plates are visible. The presence of water in these areas very probably suggest the possibility of an infiltration as well as the prospect of spending some time in a boatyard. Once ashore, haul the boat and check if the bolts of the ballast have suffered crevice corrosion. Then loosen nuts, remove the ballast and set all the parts back in place using new sealant on the whole contact surface or remove the damaged bolts.

The second possibility, definitely the most problematic one, is also the most difficult to be ascertained, especially in case of integral countermold hulls. The only consolation is that – likely – the damage is due to a collision that, of course, cannot have passed unnoticed and so the interested area can be broadly identified.

This article has analysed the checks to be performed in case water is found in the bilge. In the light of the above I think the need to check the bilge and keep it clean cannot be stressed enough. This is the only way to search for infiltrations or failures quickly and thoroughly. 

There is another consideration to make. It is probably obvious but it is important to underline that all these checks could, or better, should be made at the time of purchase of the boat. An expert consultant will, of course, do it. But, as we all know, often the purchase of a boat is negotiated autonomously and with no professional advice. So pay attention in advance, not to be lately up to your neck in trouble.

Fair winds to everybody!

Renzo Crovo

Renzo Crovo