They do say, and it is truth, that any conversation between two boaters will eventually descend into a discussion about toilets. It is that time, dear reader. I shall try to avoid being indelicate.
The heads aboard Pagan were unsatisfactory on two counts.
Firstly, the toilet itself was, not to put too fine a point on it, knackered. A marine sea toilet is a complex beast compared to the domestic variety, full of valves and seals and those valves and seals were no longer valving and sealing as they should.
The second issue was the lack of a holding tank. Marine toilets on (smaller) seagoing craft routinely discharge direct to sea. At sea, this really isn't a problem. The volume of waste discharged is microscopic and spread over a very large area and it simply adds nutrients to the water.
However, in an enclosed marina it can be a different matter and it's generally considered unpleasant to discharge solid waste in a marina.
And of course, we have a specific problem as we're only afloat twice a day and having poo on the mud alongside the boat awaiting the next tide to carry it away is simply not to be contemplated
After much cogitation, we decided to strip out the existing (and rotten as it transpired) shelf from the locker behind the heads and build a new shelving arrangement incorporating a small 25l gravity discharge holding tank
Although small, that will be sufficient to act as a buffer for a day or two between tides and when we're in a marina. It can simply be discharged on the ebb or when we get out to sea and the total quantity of waste in the tank is not so great as to cause unpleasantness when discharged on our mooring (being mostly flush water anyway)
The holding tank (top left) tucks neatly into the corner of the space and sits on a new shelf plus it's bolted back to a rail across behind it. It shouldn't go anywhere no matter how extreme the conditions.
The tank discharges to the waste seacock via a valve which, irresistibly, will forever more be known as the Dump Valve! The valve (blue handle) can be seen below the tank.
Commonly, on gravity discharge systems, the seacock itself is used but I wanted to avoid that for two reasons. Firstly, if a blockage occurs I want it to happen above the waterline and secondly I didn't want waste accumulating against a closed seacock and choking it up.
Below and to the right of the tank is a diverter valve which selects between seawater and fresh water flush. Another consequence of being on a mud berth is that we can't use seawater to flush the loo when the tide is out. And even when the tide is in there's a tendency to suck mud up into the pipework or, worse, the loo itself (which has happened and has partially blocked the flush outlets around the rim of the toilet)
To avoid any danger of cross-contamination of the fresh water by seawater or backing up from the toilet, there are no less than two non-return valves and three loops in the system.
The final loop, fitted with an anti-syphon valve, is in the pipe between the pump and the toilet bowl. (For the life of me I don't understand why people persist in fitting the anti-syphon valve ahead of the pump where it severely reduces the effectiveness of the flush)
Of course, any job of this nature inevitably involves drilling holes in the boat.
In the course of the installation, Pagan acquired two new tank vents, one for the holding tank (aft) and a second for the main water tank (forward) plus, whilst I was at it, the skin fitting for the shower discharge pump (further down the to-do list)
Also, on deck, a big hole had to be drilled for the deck pump out fitting. This was complicated by Pagan having a balsa cored deck which meant raking back the balsa and filling the cavity with epoxy - the last thing you want is water getting into the balsa core.
The final element of the installation was a brand new toilet and pump. The cost of the parts to refurbish the existing pump is about three quarters of the cost of replacing the whole lot and total replacement solved the problem of the clogged up passages in the old loo.
And finally I was able, quite late last night, to reinstall the locker front and then tidy and clean the compartment.
There's some making good of old holes still to do at some point but that's finessing that can wait until there's nothing more urgent on the to-do list
The new installation works a treat although flushing, at least on fresh water, is slightly harder work than usual which is not surprising given the plethora of loops and non-return valves
I'm implementing a strict ban on using seawater flush on our home berth to avoid any risk of clogging up the new loo
I shall also keel haul the first person to put anything they haven't eaten or drank down the bog, other than recycled bog roll*. He or she who blocks the system will get handed a pair of marigolds and told to unblock it
* Cheap recycled bog roll simply dissolves away to nothing very rapidly. Expensive quilted loo paper, whilst softer on the bum, stays intact for much much longer.
PS. A top tip from fellow sailor Keith is to use a hair dryer to soften up the hose ends. It works considerably better than the old trick of dipping the end in boiling water (especially on sanitary hose) and removes the risk of scalding yourself
The heads aboard Pagan were unsatisfactory on two counts.
Firstly, the toilet itself was, not to put too fine a point on it, knackered. A marine sea toilet is a complex beast compared to the domestic variety, full of valves and seals and those valves and seals were no longer valving and sealing as they should.
The second issue was the lack of a holding tank. Marine toilets on (smaller) seagoing craft routinely discharge direct to sea. At sea, this really isn't a problem. The volume of waste discharged is microscopic and spread over a very large area and it simply adds nutrients to the water.
However, in an enclosed marina it can be a different matter and it's generally considered unpleasant to discharge solid waste in a marina.
And of course, we have a specific problem as we're only afloat twice a day and having poo on the mud alongside the boat awaiting the next tide to carry it away is simply not to be contemplated
After much cogitation, we decided to strip out the existing (and rotten as it transpired) shelf from the locker behind the heads and build a new shelving arrangement incorporating a small 25l gravity discharge holding tank
Although small, that will be sufficient to act as a buffer for a day or two between tides and when we're in a marina. It can simply be discharged on the ebb or when we get out to sea and the total quantity of waste in the tank is not so great as to cause unpleasantness when discharged on our mooring (being mostly flush water anyway)
The holding tank (top left) tucks neatly into the corner of the space and sits on a new shelf plus it's bolted back to a rail across behind it. It shouldn't go anywhere no matter how extreme the conditions.
The tank discharges to the waste seacock via a valve which, irresistibly, will forever more be known as the Dump Valve! The valve (blue handle) can be seen below the tank.
Commonly, on gravity discharge systems, the seacock itself is used but I wanted to avoid that for two reasons. Firstly, if a blockage occurs I want it to happen above the waterline and secondly I didn't want waste accumulating against a closed seacock and choking it up.
Below and to the right of the tank is a diverter valve which selects between seawater and fresh water flush. Another consequence of being on a mud berth is that we can't use seawater to flush the loo when the tide is out. And even when the tide is in there's a tendency to suck mud up into the pipework or, worse, the loo itself (which has happened and has partially blocked the flush outlets around the rim of the toilet)
To avoid any danger of cross-contamination of the fresh water by seawater or backing up from the toilet, there are no less than two non-return valves and three loops in the system.
The final loop, fitted with an anti-syphon valve, is in the pipe between the pump and the toilet bowl. (For the life of me I don't understand why people persist in fitting the anti-syphon valve ahead of the pump where it severely reduces the effectiveness of the flush)
Of course, any job of this nature inevitably involves drilling holes in the boat.In the course of the installation, Pagan acquired two new tank vents, one for the holding tank (aft) and a second for the main water tank (forward) plus, whilst I was at it, the skin fitting for the shower discharge pump (further down the to-do list)
Also, on deck, a big hole had to be drilled for the deck pump out fitting. This was complicated by Pagan having a balsa cored deck which meant raking back the balsa and filling the cavity with epoxy - the last thing you want is water getting into the balsa core.
The final element of the installation was a brand new toilet and pump. The cost of the parts to refurbish the existing pump is about three quarters of the cost of replacing the whole lot and total replacement solved the problem of the clogged up passages in the old loo.And finally I was able, quite late last night, to reinstall the locker front and then tidy and clean the compartment.
There's some making good of old holes still to do at some point but that's finessing that can wait until there's nothing more urgent on the to-do list
The new installation works a treat although flushing, at least on fresh water, is slightly harder work than usual which is not surprising given the plethora of loops and non-return valves
I'm implementing a strict ban on using seawater flush on our home berth to avoid any risk of clogging up the new loo
I shall also keel haul the first person to put anything they haven't eaten or drank down the bog, other than recycled bog roll*. He or she who blocks the system will get handed a pair of marigolds and told to unblock it
* Cheap recycled bog roll simply dissolves away to nothing very rapidly. Expensive quilted loo paper, whilst softer on the bum, stays intact for much much longer.
PS. A top tip from fellow sailor Keith is to use a hair dryer to soften up the hose ends. It works considerably better than the old trick of dipping the end in boiling water (especially on sanitary hose) and removes the risk of scalding yourself
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