So where’s the water coming from?
I own a 45ft Sea Otter fitted with a Vetus 34 engine and a bow thruster. The boat takes on about 250-300ml of water into the cabin bilge every day it moves. The water sits under the stern companionway step. If the boat is static, no water collects in the bilge. The engine bilge is dry. I have tested every
Qwater source: filling and overfilling the water tank, shower head and waste. I have coloured the shower waste water with dye.
It is not linked to heavy rain. We do get quite a lot of condensation but not in the summer. The water is cloudy but odour and colour-free. Have you come across this before?
Have you checked the bow thruster tube and weed hatch for leaks? If the toilet is a pump-out the holding tank might have a leak and ‘self-seal’.
If you have eliminated leaks from the shower, domestic water and are ignoring condensation, the only other ways water can get in are from the
Astern gland, the cooling system, leaking windows, the heating system, or from a leak in the hull or water tank. Leaks from the cooling or central heating system should have a slightly sweet taste of antifreeze but only sample the merest drop on a finger-tip – antifreeze is poisonous.
Most Sea Otters use a PSS shaft seal and I would not be surprised if it would leak if the shaft was running a little out of true or the rotor is not correctly tensioned on the shaft.
This leaves a leak from the hull, bow thruster tube, weed hatch, or water tank. I would suspect the bow thruster or hull. Very small leaks in steel boats’ hulls can ‘self caulk’ and block themselves with rust. An aluminium boat may well ‘self caulk’ but it will not rust, so when the leak is subject to vibration and/or water flows, the particles may be drawn out of the crack so it leaks again, re-sealing when the boat is stopped.