Project: Blackwater line replacement...

[bstreep]

Ever since we bought this boat, we've known this project was "in the works". Old lines have crystals on the outside. We've just had other priorities, until now.

We bought 50' of Trident, top-of-the-line hose, for the job (good deal, too!). I've done this job on a friend's 40' trawler, so I'm familiar with the job. But, I'd like to make sure we do this as cleanly as possible - since last time HE was the helper, and this time, the Admiral is the helper...

We have good access to holding tank pumpout - we can go over to the new slips at the marina, and flush a few times, with little or no effort/pain.

We have a typical system with a fresh water electric toilet. Effluent runs to a "y", and goes either to the outside, or to the holding tank. Holding tank has a "y", that goes either out thru the deck fitting, or to a hand pump, thru a thruhull. Ovbiously, we use the holding tank.

So, with those familiar with this job: What should we do as prep? Fill the tank, run bleach, vinegar, or something else thru it first? Vodka (ok, just kidding)? Any thoughts?

TIA,

[Pblais]

Flushing it just can't hurt but the problem is the old hose has permeated. When we did the last boat with the system totally empty the hoses smelled bad and that was from the outside of the hose. At least you can keep the surprises from dripping out of the hose ends as you remove the old hose. You need to replace as you go or you'll never get it back together.

Rules of the Admiralty:

The Admiral knows when the job stinks so don't ask.

[roger.waite]

Not an option if you live aboard, but last time I replaced my blackwater hoses I flushed the system well, then just left it a month for the bugs to do their thing. There was no doubt when the hoses came off that I was working on a sewage system, but the smell was not overly strong and spillage was reasonably clear.

If you were going to add a chemical sterilant, the time to do it would be after the bugs had worked their majic, and there was less faecal matter to absorb it. Just be careful with what chemicals you use. There are seals and valves that could get damaged ... but I am not sure of my ground here.

Best wishes for a smooth, trouble free job.

[MarkJ]

Originally Posted by bstreep

So, with those familiar with this job: What should we do as prep? Fill the tank, run bleach, vinegar, or something else thru it first? Vodka (ok, just kidding)? Any thoughts?

TIA,

Hi Tia,

We bought a large box of surgical gloves and have about one million servittes handy in stacks. A quadrillion of zip-lock bags too.

We line as much of the work area with plastic rubbish bags with paper towels laid on top.

We have all the tools we need (and others we dont need) all laid out.

The 'active' person takes control and the 'receiver' stands astern of the active ready to bag the refuse and hand the tools etc.

Then we just focus on the result and hoe in!

All the best


Mark

[Pblais]

I like Marks approach.

Pouring chemicals into your system isn't really a good idea. Too many things won't like them. When everything is all nice and new and the vent line is clear the really hideous smells are from anaerobic oxidation (when there is no fresh air available).

When waste oxidizes aerobically the small is not as hideous even if still not sweet and fresh. If the little critters are alive they oxidize aerobically and makes less smell. When the waste sits in the curls and low spots of the hose or in a tank with clogged vent is when the bad stuff gets made. Flushing from both ends with clean fresh water followed by a pump out should clear the worst of the worst. I would run a lot of fresh water through the head(s) and even top off the waste tank before pumping it clear.

Once the hose is replaced don't be putting hash chemicals in the tank. A little vinegar to deal with the salt buildup if you flush with salt water is OK. Things that work better for one purpose are not always better for the overall system. Keeping those hungry waste bugs alive is better for your smell.

[bstreep]

Thanks for the advice, folks. The tank is currently sitting, with a bacterial culture eating it up. Ever since we started doing this, it's helped a LOT - that and making sure the vent is clear.

We are not liveaboards. I'm inclined to pump it clean, flush fresh water from both the head and the waste pump out on deck. Maybe flush twice?

Thanks for the ideas on bags/baggies/towels/gloves (and probably zip ties). We keep all of those handy anyway.

[Chief Engineer]

When I take a hose off, I stick a wad of paper towels into the hose.

Baggies with duct tape on the ends(esp. if you have to carry it thru the boat)

And a bandanna on the face...it is more of an aestheic thing...if you get splashed

[bstreep]

Ooooh. DUCT TAPE! Gotta remember that one too!

Thanks, Chief.

[MarkJ]

Guys its not that bad.

Just jump in and do it. Wear a diving mask if you like, that'll knock out the smell.

But the smell etc just ain't that bad!

Hospital nurses have it much worse all day every day.

I certainly don't shy away from the blockage job or maintenance now.