How much bilge water and fuel leak is too much?

[Boater On Thames]

Dear Mates,

I am a beginner. Just bought a 42 feet fly ridge last year winter. And found the bilge always has water and diesel mixture. I cleaned around 40 L mixture total within the last 3 months period. About 70% water, 30% diesel.

So, it's like 13.5 L every month, about 10 L is water, 3.5 L is diesel. Is this too much? Thanks mates.

 

[Portofino]

The diesel is .
Water not so bothered - rain and other leaks .

Find the source and fix the diesel .

 

[jrudge]

You really need to find and fix the diesel leak

Options are the tank , fuel lines or the system post the pump

 

[rafiki_]

Check the water pump. The seals can leak due to the forces on the shaft. Diesel leak likely to be fuel line.

 

[Boater On Thames]

Thanks mates.

I now only find a suspect diesel leaking from the starboard tank. But not obvious, so I will keep monitoring from today. Hopefully not the tank!

The tank is under the shower room, and it's unaccessible! Just used my under water camera with a selfy stick to take a look under the floor, the tank all dry on the surface, fuel pipes and fittings. The worst case could be on the bottom of the tank! Hopefully not. Because that will be impossible to fix if that is the case unless I remove the shower room, floor and lift the tank up!

 

[markc]

Agreed with others, find the diesel leak. Diesel stains so inspect the bilges carefully and you may be able to trace it back.

 

[jrudge]

Good luck. Water is also a bugger to find the source of on a boat

Obvious - salt or fresh.

The time honoured method is talcum powder and hopefully you can see trace lines showing where is came from

 

[kashurst]

what boat is it? another owner may be able to suggest more specific ideas about possible leak source and solutions.

Is there enough room around the tank to lift it up a bit if you release the holding straps and put some paper underneath to see if its leaking?
The water could be from the sea water pumps on the engines and /or the stern glands where the shafts go out the bottom. If it's rain water that can be a sod to find but doesn't matter too much. Check all the deck drains are clear and connected to the external skin fittings
Does the drinking water pump come on every few hours for no apparent reason? If so check out all the on board drinking water pipes - not uncommon to have a leak at a joint.

 

[Boater On Thames]

The boat in fresh water.

The boat has two big tanks, each 200L, so no room to move or lift it up. I am now putting some dry tissues on all the suspicious position to see where the diesel leaking from. This might get result tomorrow.

 

[simonfraser]

blue roll is good for this as it stains nicely when wet or dries crinkled.

p.s i would say any amount is too much, you need to know what leaks, if it is wet already it's impossible to figure out what is going on.

 

[Bandit]

You should not have any diesel in the bilge at all.

Water. depending on the sterngland, if a packed gland a drip is normal, if you have modern dripless seals you should have no water from sternseal in the bilge.

So where is it coming from?

 

[Assassin]

Can you get access to the top of the tank and does it have an inspection hatch? if so then if you can drain the tank and clean it you can get various resin based compounds in liquid form which are mixed and you pour them into the tank and it seals the bottom, but you really need to be careful of any baffles and use a hose to pour your mixed resin into so it goes straight to the bottom of the tank and settles, and not on any baffles or fittings.

 

[Boater On Thames]

Thanks mate. Yes, it has a hatch. Your idea is brilliant! I might give it a try eventually. It just the tank has three quarters diesel in it which about 150 L at the moment! Don't know how to drain and what container can hold that much!

 

[simonfraser]

draining / storing it is one thing
getting it clean enough for the sealant to stick, that would be the tricky bit in my opinion ....

and b4 you do all that, is it def the tank bottom, or connectors that leak ?

 

[Boater On Thames]

You are right! The only fitting I can reach through the little hatch (just about 8" circle hatch) is the filling pipe and a 3/4" pipe to the engine. Seems like not easy to clean such a big tank!

 

[Boater On Thames]

I still investigating where the leaking from. All the connectors looking dry and good. The only wet little stream I can found is a 1" hold on the bottom next to the starboard tank room.

 

[simonfraser]

dry it out and see how big the leak is there
could be a spill from somewhere else
took me 2 yrs to find All the leaks in the bilge of my boat ....

 

[Deleted User YDKXO]

. About 70% water, 30% diesel.

Diesel is lighter than water and sits on top so it always looks like there's more diesel than there actually is but you should try and find the source of it because many local authorities take a dim view of diesel contaminated bilge water being discharged overboard (rightly so)

Do your diesel tanks have drain plugs (for draining the bottom of the tanks)? Might be worth checking that they arent leaking

 

[powerskipper]

when you clean it out, try and dry it off after, then put some absorbent mats down. this should give you an idea of where the leak are coming from if it under the engines.. If you put some kitchen roll around areas ie pipes or joints that you think might be leaking or close to or under .(do not do it where it gets hot!) you may be able to see where its leaking from too.

 

[Boater On Thames]

Thanks mates. Will try.

Here you reminded me one more question: where can I discharge the diesel water mixture? I keep all that 40+ L bilge mixture liquid in three containers on land. I will never discharge them to the river. Where can I discharge or recycle them to?