Monthly Archives: July 2016

Classic Boats and Fireworks


Water, water everywhere…

As our Caliber 40 was one of the models built before the Caliber 40 LRC (Long Range Cruiser), it does not have the tankage that the newer model does.  This means that from the factory it came with a 60 gallons diesel tank and 150 gallons for water (in one 80 gallon and one 70 gallon tank). We wanted to get more range for diesel and so had the intention of converting one of the water tanks to diesel and installing a water maker to supply the one remaining water tank.

The closest water tank to the engine was the 80 gallon tank, so once completed we would have 140 gallons of diesel and 70 gallons of water with the ability to top up the water tank from the water maker whenever underway in clean salt water.

As we are no planning a crossing till next year we don’t really need the larger diesel capacity at this point. ¬†Last year some friends of ours from TMCA, Chris and Jerry, won a Spectra Ventura 150 Deluxe water maker at the Southwest International Boat Show in Kemah. ¬†They had no use for the package and so we agreed on a good price for all parties and had the unit we were looking for. ¬†It took 7 months before I got around to carrying out the installation due to other pressing projects.

First was the planning. ¬†I had to work out where to put all the pieces. ¬†The package is a modular design and so you have some latitude with where everything goes. ¬†The major parts are…

  1. Clark pump (pressure intensifier used to force the salt water through the reverse osmosis membrane)
  2. feed pump module (Shurflo pump and fresh water flush filter)
  3. accumulator
  4. sea strainer (used to remove large items from the seawater supply)
  5. 5 micron pre-filter (to remove all other solids)
  6. product sampling valve (used to divert product water for testing  before sending it to your tanks)
  7. gauge board (flow and pressure readings for the water maker)

The noisiest component would be the feed pump module so I wanted to place that where it would disturb us the least.  Almost all parts could be possible sources of leaks and so would have to be placed in a part of the boat that could drain to the bilge.  After much back and forth I decided to place all the major components in the lazarette.  The Clark pump would go on the existing shelf just outboard of the lazarette hatch.  The feed pump module would go on the forward wall next to the shelf.  The sea strainer would go below the feed pump module and the gauge board would be mounted above the breaker panel at the nav table.  This would put the connectors to the gauge panel in the lazarette just above the Clark pump.  I would run the product piping from the lazarette, down beside the engine and up under the sink where it would connect to the sample valve.  From there the product piping would go to a spout next to the sink and forwards to the 1 water tank.

The galley already had a pull up hose attached to the faucet which we never use.  I therefore removed that and used the existing hole for the new product sampling spout.  This would allow us to run the water maker and drain the sample product directly into the sink until the water quality was good enough to divert to the water tank.

This proposed design did pose problems… naturally. ¬†First was that the inverter/charger used for shore power hung directly below the shelf I wanted to install the Clark pump on. ¬†If there were any leaks, and water reached the inverter/charger, this could cause a dangerous situation. ¬†I therefore painted the shelf with several coats of bilgecoat to seal the shelf surface. ¬†I also used butyl tape to seal any penetrations used to bolt the Clark pump to the shelf. ¬†There is a drain hole at the corner of the shelf, far from the inverter/charger and so this, along with the other measures, would hopefully suffice.


Clark pump installed on the lazarette shelf

The thru hull used to pull in sea water should be mounted as close to the centerline of the boat to ensure that it can pull water no matter how far over the boat is heeled.  The best place to drill this hole was under the cupboard lid in the lazarette.  There was an existing hole in the cupboard roof which I could use to run the hose from the thru hull to the sea strainer.

The Shurflo pump is mounted to the pump module with rubber vibration dampeners but is still quite a loud pump.  I therefore added rubber dampeners to the module when attaching it to the wall to reduce the amount of vibration as much as possible.


Pump module mounted on the lazarette forward wall

The fresh water flush is used to flood the Clark pump with fresh water after water production.  This educes the possibility of bacterial growth between runs.  This requires a fresh water supply to fed the charcoal filter used in the process.  I tied into the Quest piping that supplies the swim platform shower.  I brought this under the shelf  to the filter.  That can be seen in the left of the picture above.

The hose from the sea strainer to the feed pump is attached with plastic fittings.  As I knew there would be heavy items in the lazarette, which would shift around during heavy seas, I fashioned a cage around those parts to protect them.

watermaker 009

protective cage between sea strainer and pump module

The hose coming out of the feed pump leads under the shelf to the pre-filter which is attached to the aft end of the shelf right next to the accumulator.  From there the hose goes to the gauge panel and Clark pump.


I attached the product sampling valve off to the side of the door for the cupboard under the sinks.

To get the water into the tank, I drilled and tapped the inspection plate in the roof of the tank and added a quick connect fitting so it could be unattached at any time

watermaker 018

As I had the inspection plate of the tank off, ¬†I also removed the plate from the other tank and pressure washed both tanks to remove a few years of “gunk”. ¬†I dried out the second tank so it would be ready when it was time to plumb it for diesel.

I bought one other item to improve the water maker. ¬†Spectra sells a Z¬Īion filter. ¬†This will stream silver ions into the water supply when flushing the unit after use. ¬†These silver ions inhibit the growth of bacteria and mean that you can leave the water maker without use for up to 30 days. ¬†Without this, the water maker must be flushed at least every 5 days. ¬†It is a direct replacement for the regular fresh water flush filter and required simple wiring into the feed pump power supply.

Underway we can now turn salt water into fresh water at a rate of 7 gallons per hour with a current draw of about 8.5 amps.