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Updated: Jan 2, 2023

Again and again I find these deficiencies on used boats.

Each survey produces unique findings, and each boat has its particular characteristics, however, certain issues are common to many boats. Here is a list of the 5 most common deficiencies I have found in my surveying work.

1. Seized or Very Stiff Seacocks

So common are malfunctioning seacocks that I always assume they are deficient until I can prove otherwise. Seacocks are the valves connecting through-hull fittings that either let water into your vessel (machinery cooling water, seawater faucets) or allow water to drain out (grey water, sewage discharge, cockpit drains, etc.). To properly maintain the plumbing and machinery connected to the seacocks, and to have control over the watertight integrity of your hull, the seacocks must be easily opened and closed. If any part of the plumbing connected to a seacock is compromised the seacock must be shut to both stem the leak and effect a repair. Very often however, seacocks are a neglected part of the boat, ignored until closing them becomes critical.

The seacock valve on the sewage discharge through-hull shown below has been so neglected the handle has rusted completely off. In the event of a malfunction in the plumbing downstream, this valve cannot be closed to facilitate the repair. Thus, a simple repair could become an expensive haul out, or worse, a flooded and sinking boat. This one is particularly bad, but I see seized seacocks all the time that appear just fine until you try to close them and realize they haven't been exercised in years.

2. Poor Battery Installation

Most boats rely on DC 12 or 24 Volt battery power for many critical functions on board. Battery installations can be quite simple with just one or two batteries providing start and minimal house power, or they can be quite complex, with many installed DC components requiring power. Regardless of the complexity of the system a few fundamental requirements of the battery installations remain constant. The image below shows a small two-battery bank with four of the most typical installation deficiencies: the batteries are not secured; the ungrounded battery terminals are not insulated; the conductors are not arranged with the largest on the bottom of the terminal posts; and a wing nut has been used to secure one of the conductors.

3. Non-functioning Bilge Pumps

Bilge pumps are obviously a critical component of any boat's safety equipment. When you need them, they better work. Much like the seacocks mentioned above they tend to be located in awkward and seldom viewed locations on most boats. As a result, they are often neglected and ignored until their function becomes critical. Commonly, when they are not functioning the issue can be traced to the electrical connections; wet locations, corrosion, poor installation, and pinched or cut wires are all conditions that can cause the connections to fail. A typically awkward-to-maintain installation is shown below.

4. Missing Vented Loops

Numbers four and five in my list are examples where a piece of equipment is not broken or malfunctioning, but missing altogether. Usually, the absence of the equipment is simply a result of ever changing and improving standards, rather than deliberate removal.

Vented loops, a requirement on many wet exhaust systems, raw water supply hoses, and sewage discharge hoses, are very often not installed equipment on older vessels that were subject to less stringent standards. Unfortunately, often the lack of such installations are accidents waiting to happen. A vented loop, or anti-siphon, provides an above-waterline break in plumbing leading to a below-waterline appliance like an engine or marine toilet. Without this anti-siphon break, sea water can back flow from the seacock through the appliance and potentially flood the boat. In the case of an engine, a back-flow of seawater can cause very significant damage and render the engine inoperable. Below is a proper vented loop installation for a marine toilet - one for the raw water intake, and one for the sewage discharge.

5. Missing Smoke Detectors & Carbon Monoxide (CO) Detectors

Like so many of us, boat owners are susceptible to pulling out the batteries on their alarms to silence the low battery warning. As a result, despite good intentions, many Smoke and CO detectors end up forgotten in a drawer with the batteries removed. All vessels over 8m in length with overnight accommodations are required to have smoke and CO detectors. A good practice is to replace the batteries at the beginning of each boating season.


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