On Board water runs black?!

[sailor john]

Hi all,
We have just commissioned Mad Hatter for the new season and I have an interesting issue with the water system.
The water flows intermittently clear and clean and then goes black for 30 seconds or so, then runs clear and clean again, then back to black. And so on.
Any ideas what this 'black' colouration might be? It seems to be from both hot and cold water supplies, whether dock supplied or water tank supplied. It runs the same to sinks and heads.
I have water treatment sitting in the tank now. Any ideas are appreciated!

Sailor John

 

[sunchaser]

You might try:

Is the black stuff slime or sandy grit? If slime:

1. Drain your water and heater tanks completely to the bilge
2. Partially refill and drain again about 3 times
3. Fill and let sit for an hour or two with about 1 cup of bleach for each 100 gallons while flushing through the system.
4. Drain and repeat #3.
5. Add a "purifier" and follow system odor - assess need to retreat in a month or two.

If grit, flush tanks several times until grit gone. You may want to buy a hose end filter prior to refilling as problem may be source of water

 

[Carolena]

Just guessing, but could it be the rubber diaphram in the accumulator deteriorating?

 

[fryedaze]

My money is on the accumulator. Mine did the same thing only I had rusty water due to the inlet fitting corrosion. When I cut the accumulator open the bladder was deteriorated and there was black material that came off its surface.

 

[sailor john]

Evening all!
Thanks for the input thus far.
Just to be clear, this is happening while hooked up to dock water; I don't know if happens with the pressure pump simply because its not commissioned yet.
So...I think that lets the pressure tank off the hook. (maybe?)
Interesting comments re the hot water heater...It could be original and dirty I guess.
I can flush the system all day long and see if that helps to work things through.
Stay tuned! and thanks for your comments all!
Sailor John

 

[Aquabelle]

Do you have cartridge water filters in your system? Could be caused by a collapsed/long-forgotten pleated filter cartridge

 

[sailor john]

Aquabelle, that's an interesting thought....could be. Its the only thing that all water goes through, hot or cold, dock pressure or pump pressure.
Sailor John

 

[sailor john]

Just an update...Aquabelle, looks like you win! I found and took out the Everpure in-line water filter. I turned it upside down and the water ran 'black' out if it. I have no idea how old it is, but it sure looked old. (I've had the boat for 3 years, and I didn't know it was there!)
Sooooo...I ordered and replaced the filter unit ($100.) and everything runs clear and clean as a possible! Thanks all for your inputs! A great call out by Aquabelle!
Sailor John