Dufour slowly sinking

I seem to be continually pumping out my bilges about a couple of litres a week. The boat is a dufour 425 grand large. I noticed that the stanchions were lose and spent most of yesterday removing all the soft fittings to get to the bolts and have tightened them all. Also notice water discoloration in the woodwork where the stanchions are located. Could this be the cause of my slow but inevitable movement to davy jones locker?

Any ideas welcome.

Thanks

The stained woodwork indicates leaks and I would rebed the fittings and not just tighten them up. I would also go over all the other fittings such as hull deck joint bolts etc. question, does the water appear when it has not been raining? Also worth checking things like the various plastic drain fittings that are in places like cockpit lockers and can be subject to fracturing. Had one fail on a friends boat when it was kicked by the outboard being put into a locker.

Yoda
 
Has the engine been running while you are on the boat? If so, check water pump, the cooling circuit and also see if there is any ingress at the stuffing box.

Also, if the wood is stained check to see if there are any leaks through the windows. If there are any, they would probably have dried by the time you are on the boat but the wood would still have been affected.
 
I tasted my bilge water recently trying to track down a small leak then remembered our boat is now moored in fresh water.
 
Dufours were for a time using brass skin fittings and valves, if your boat is 5 years old or more these can leak, they should be carefully inspected and operated to ensure they operate freely.

The life of brass is normally 5 to 7 years before problems start. They are often marked with CW617N.

Should you have any leaks, build up of lime scale fur around a joint etc, consider changing that valve.

If your boat has brass valves and skin fittings and is over 7 years old consider changing the lot.
 
Thanks everyone for your ideas. To respond to your questions;
1 She has just been out the water and had all seacocks checked (even she is a 2008 vintage) and keel resealed. I will, however, look at the internal plumbing to the seacocks.
2 Have tasted the bilge with tongue and hope I have not sampled the wife/kids wee, battery acid or coolant, my taste buds tell me that it's fresh water! I will also buy a salinity kit from a pet shop to back up my ageing taste buds.
3 The pump does not go off unless a tap is turned so pretty confidant there is no leak on the pressure side of the system. I will however, turn a tap on with the pressure system off when next leaving the boat.
4 Due the flat bottom nature of theses type of boats the bilges are very shallow and only fills from one direction (not very helpful!)
5
 
I have a Dufour 385. I had one leak from the pressurised water system where the plastic pipe leaves the water heater. Another through a stanchion bedding. Both easy to fix once the cause was discovered, but, as you say, the flat bilges meant that in the week or so before I discovered the leak, the copper lightning conductor (I guess that's what it is) connecting the mast to a keel bolt was immersed and had corroded.
 
Thanks everyone for your ideas. To respond to your questions;
1 She has just been out the water and had all seacocks checked (even she is a 2008 vintage) and keel resealed. I will, however, look at the internal plumbing to the seacocks.
2 Have tasted the bilge with tongue and hope I have not sampled the wife/kids wee, battery acid or coolant, my taste buds tell me that it's fresh water! I will also buy a salinity kit from a pet shop to back up my ageing taste buds.
3 The pump does not go off unless a tap is turned so pretty confidant there is no leak on the pressure side of the system. I will however, turn a tap on with the pressure system off when next leaving the boat.
4 Due the flat bottom nature of theses type of boats the bilges are very shallow and only fills from one direction (not very helpful!)
5

Is your mast deck stepped? If not it could be rainwater seeping down the inside of the mast. Easy to test for - just remove a few floorboards and check for trickles of water radiating from the mast base during a heavy shower.
 
Sorry, fingers got carried away;
5 I will check the locker drains and look for damage.
6 She sits high out of the water when under power so pretty sure its not coming from the stern.
7 I will see if the amount of water decreases since tightening up the stanchions. I will try seal them deck side as to remove them all would be a hell of a job given access to the nut is through all the head lining and cupboards.

Thanks again for all your advice
 
Is your mast deck stepped?

Pretty sure all "modern" Dufours (i.e. all the "Grand Large" and "Performance" ranges built since the early noughties) are deck stepped.

Edit: Appears I am wrong - looks like the most recent performance ones are keel stepped, but mine (2005 vintage) is deck stepped. All of the current Grand Large range are deck stepped.
 
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I seem to be continually pumping out my bilges about a couple of litres a week. The boat is a dufour 425 grand large. I noticed that the stanchions were lose and spent most of yesterday removing all the soft fittings to get to the bolts and have tightened them all. Also notice water discoloration in the woodwork where the stanchions are located. Could this be the cause of my slow but inevitable movement to davy jones locker?

Any ideas welcome.

Thanks
Sometimes just tightening up the Stantion is a short term fix. You may need to rebed them properly if the still leek.
 
Sometimes just tightening up the Stantion is a short term fix. You may need to rebed them properly if the still leek.

My "guess" is that the stanchions are a red herring unless the woodwork discolouration the OP is referring to is on inside the boat as opposed to the external decks. Even then condensation could be the culprit for this. In fact I can't for the life of me see how the stanchions could let in so much water without it being extremely visible and doing a fair amount of other damage.
 
Tigger is a Dufour of the "Classic" variety. Eight or so years after built she started leaking really badly through the screws that hold the toerails and stanchions. The only effective solution was to remove all the rails and stanchions an rebed them with more generous dollops of sealant (can't remember what variety). I am holding my breath about when they will start leaking again. I don't understand why the builders did not use a proper glassing in procedure to make the toerail fixing properly water tight "forever".... really bad design feature, IMHO.

:disgust:
 
my taste buds tell me that it's fresh water!

If it is fresh water then my money is on the output side of the calorifier. You say the pump does not operate but if like mine, the pump can run very slowly without making a noise if their is a pin-prick hole in the output pipe. This is most likely within a few inches of the output so tie a rag round the pipe loosely and see if it gets damp. Also, is there a leak when the pump is actually off, but bear in mind a slow leak can take a while to dribble down to the bilges especially if the small holes from the hull under the calorifier through to the bilges are blocked with bits of rubbish.
 
Dufour 36 Classic,had most of the issues mentioned,except stanchions/toerail issues.One issue as mentioned is the dribble from the pressure valve on the calorifier,which seems to be a feature of over pressure in the pump,and as OP says opening a tap to relieve this seems to reduce the problem to manageable levels.Some have replaced the pressure relief valve to no avail.Reducing the pressure in the expansion vessel seems to help alleviate leakage,but the shower may pulse more in use.
 
My experience with a Dufour was with leaks in several places: portlights, genoa track, hatches, chainplates.
Whenever I stopped one leak there was another one starting elsewhere. For a while I was also confused because I saw the water clearly coming in when it was raining, but the water accumulating in the bilge was salty. I had no leak around the engine or seacocks and thus this was puzzling.

Eventually I removed all the boards, cleaned and dried the bilge and I sprinkled cinnamon powder all over.

The salt water was coming from the keel bolts.
 
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