On the Job

Guide to Understanding the Filters on Board

21 May 2021By Capt. Mx
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Written by

Capt. Mx

Still pushing water, having enjoyed and excelled aboard square riggers, Whitbread Maxis, the world cup circuit when there were only 7 boats, America’s Cuppers, 12M, modern classics, real classics, salvage, racing, passage, refits, builds and more, for 38 years, 54 Atlantic crossings, 48 world championships, and a few stories more. I enjoy the serenity and clarity that a life between the blues offers, washed by wind and waves, where all that remains is the simple truth of all things, questions for all things technical, and acceptance of all things magic. 

As we waltz and wander across the decks and docks, many are unaware that the environment is rather complex. There exist filters of varying types all around you — on deck and certainly below.

On deck, you may wish to filter the water that fills your tanks, so do some reading to get yourself up to date on the new tech and what the market offers (not always the same thing). In all systems, consider the pressure available, the density of the fluid or gas, the environmental challenges, whether the filter may be washed and reused or not, and several other factors that best determine what filters or strainers to use while docked, at sea, and for which system.

Your water may come in from a spigot on a cruising dock, a pipe on a commercial pier, or at times from a truck, so be prepared and have back-up cartridges or cleaners as required so you don’t run short — the water quality aboard affects the boat and all aboard (including your own efforts).

Become competent in assessing issues due to poor filtration of fuel or water, and learn how to ensure quick changes of these essential elements so the guests can go back out to play. Having a spare fuel filter or more for each engine aboard is wise.

Should you wash down with dock water, you must first test for sufficient pressure to allow an inline filter. You can, nevertheless, wash down without a filter and use product from your watermaker to assure a very clean and sediment-free surface once complete. Coordinate with your chief engineer to discuss which tanks are dedicated for product water and, if at all, the tanks for dock water.

Using product water, you will find an extraordinary difference after chamoising down as product water removes virtually all residue. I know a man who used product water exclusively as he went around the world and at the end, his vessel looked almost better than when purchased new a few years before. Do not forget the other filters that may have you rue the day. This includes the fuel filters for all your small engines, inline, or cartridge type; make sure you have a box of each as conditions for fuel in many places are less than optimal. You should also require one or two air filters (at most) for the season — I tend to prepare for the things I wish to avoid as much as those I wish to achieve. Become competent in assessing issues due to poor filtration of fuel or water, and learn how to ensure quick changes of these essential elements so the guests can go back out to play. Having a spare fuel filter or more for each engine aboard is wise.

Maintenance is mostly based on hours of use, so keep your logs up to date. You’ll have to change filters (including the oil filters for the small engines aboard). Again, prepare well for hard use during the season. Be sure to have spare units and the tools required to remove and ensure the burned oil is recovered without incident for future deposit in the used oil tank aboard or ashore.

Coordinate with the chief engineer and follow his lead on this. You may have to change filters in the air handlers, watermakers, or an abundance of other possibilities, so I suggest you understand how things work and familiarize yourself with your part in it all — otherwise, there’s no reason for you to be aboard.

This article originally ran in the May 2021 issue of Dockwalk.

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