Water in bilges

cagey

cagey

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Is there a test to determine the source of water in the bilge.
Am reluctant to taste it as boat is used for charter and the thought of tasting someones pi.s is revolting.
I am hoping there is a chemical test ie. potassium permanganate , litmus paper etc to ascertain type of water in bilge ie sea, rain, excreta , fresh as in basin overfilling/ calorifier expansion or grey ( shower, washing, cooking or washing up ).
Thanks

Keith
 
If you are in doubt as to the nature of the water in the bilges. Then I would err on the side of cation and pump out as much as possible then flood them with sea water and pump out several times. then finish with a solution of bleach.
 
The standard test for chlorides is silver nitrate, which will react with the salt and deposit silver chloride, making the water go cloudy. The test has been carried out by ships' engineers for centuries, to detect any contamination in boiler feedwater. There's a description here.

How easy it will be for you to obtain some I could not say. I suspect it might be far easier to dry the bilge out completely and monitor future flows.
 
Yes silver Nitrate is a great test for 'salt' but is rather sensitive for this use IMHO (likely to give a positive from any salt contamination) - I would go with the evaporation test - put in jam jar on radiator and see how much salt left (you could also do simerlar with seawarer and get an idea of what 100% saltwater looks like for the same volume. With accurate volumes used and accurate weighting - could calculate % sea water (?)

Other answer is specific gravity measurements - then could quite accurately calculate % sea to fresh

but pump out - lift everything up/ open any access panels and spend some time on-board with a torch and come kitchen roll to dry anything that looks like water is getting in - if nothing - try again on a rainy day.
 
Surely you don't need to know what it is - why not pump it out, clean up and wait and see. Any water which appears subsequently will be sea water or rain water or something you have produced on a more personal basis, so you might be less averse to tasting it!.
 
Rogerdog is right - Silver Nitrate test is far too senistive. We use it for detecting chlorides on ships tanks before loading Glycol / Methanol / and other sensitive products.

As to SG or Density measurement - you can discount that one as well particularly in harbour waters - as depending on location and outfalls / discharges to the harbour you can see densities of less than 1.000 (SW is theoretically 1.025, FW is theoretically 1.000).

The place of radiator idea may initially sound daft - but in fact is quite reasonable.

Another way is to measure conductivity of the water ... FW pure is zero ... SW is good conductor. Water with p**s in is also a good conductor !! But that needs a better instrument than a multi-meter !
 
Dont know if it helps but my last boat had a leak and i hunted high and low to see what it was. I did the taste test and was not salty. Then I filled the water tank with a small amount of cake black cake dye, and the waste water with red cake dye, I looked at the water in the bilge after a few days and nothing red or black just water. Then I cleaned the bilge and worked on the weather and after 2 days of rain there was still no water. that day I flushed out the water tank put hose in to fill up and turned on a tap, and yes water in bilge.

I found the leak it was the air hose on the the water tank leaking tighten it and it worked.
 
Take 3 jam-jars: put salt-water (ex-oggin) in one; fresh tap water in the second, and your suspect water in the third. Chuck an equal amount of iron filings in each, keep 'em in a warm room and wait for a day or two. By visually comparing the test sample with the 2 controls you should be able to make a judgement of whether salt is present in your sample - or not.
 
Is it the overflow from your calorifier? These sometimes just discharge into the bilge as on my boat so I fitted a hose to lead it into an old plastic bottle which I empty aboult twice a year.
 
You can spit in the water. It will either stay together or seperate out depending on whether salt or not and that tells you which it is. I can't remember which way round but easy enough to find out.
 
For heaven's sake just dip your finger in and taste the bloody water. Health and safety advice aside the chances are you won't bloody die! Never happened in Nelson's day.....
 
If I remember rightly, a fresh egg will float in sea water but sink in fresh. If the egg is not fresh, then it may float in both, but it will float higher in sea water.
 
If it's salt - you have your answer

If it's drinking water that's also plain.

From your description, it's not going to be determined by tasting it. So clean down and check to see if more water accumulates. Baby nappies are great for taking care of small volumes of water.

PS Human urine is drinkable from the health point of view - anyway you'd only ingest a minute amount if you tasted and spat. It will not cause you health probs, but the risk of other contaminants including benzines should deter you more. Much more.

PWG
 
Well, I'm still alive:

Surveyor found water (identfied as salt, so he tasted it) in a section of the bilge near a keel bolt, and recommended further investigation, and postulated that it might be coming up past the keel bolt, meaning the keel would need to come off to be re-bedded.

I dried it all out, and it would stay dry for ages, then for no aparent reason fill with water again, sometimes coinciding with sailing the boat, sometimes not. I tasted it, and it was definitely salty. No sign of it coming through the keel bolt, though.

I changed the pump on the heads (because the casing was cracked, but not really leaking), but when I put it back together, I found that the base of the heads was cracked too, and had been leaking into a channel in the bilge which lead forward to the compartment around the keel bolt...

YUCK!

New Jabsco, and the bilge has been dry ever since /forums/images/graemlins/tongue.gif

Andy
 
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