The compass's importance to your boating safety cannot be overemphasized. As such you need to be proactive in maintaining its viability. Cleaning and polishing it to remove dirt and salt spray, protecting it against bumps and knocks and eschewing harsh cleaners are, of course, important. Even more important is checking the integrity of your compass prior to each and every outing. A failed compass can mean the difference between an enjoyable day on the water and a disaster in the making.

The pre–departure checklist for your compass should be both visual and physical. Let's start with the visual. Can you see any bubbles under the glass? Although a small bubble may not present an immediate problem, it is an indicator of a fluid leak and as such, can turn into a very big deal. Most of the time, such leaks are gradual and you can safely wait to replace your compass until the bubble becomes suitably distracting, but sometimes times a seal or diaphragm gives way more explosively, which leaves your boat minus a working compass. At the very least, you want to monitor the bubble carefully and have a backup compass available. To be on the safe side, you'll probably want to replace the unit as quickly as possible.

What about fluid color? As a compass ages, fluid breaks down, causing plastics and rubber to degrade and turning the once–clear fluid milky, rusty or otherwise darker. You may even note residue on the inner surface of the dome and on the compass card.

Look for stress fractures. If there is no leak, you don't necessarily have a problem that has to be fixed immediately, but you'll need to monitor closely. Multiple stress fractures that spread in such a way that they meet and encircle the dome are of more immediate concern because they may presage a rupture.

You also need to check the physical performance of your compass, by taking it off the boat, if possible. Begin by checking the spin, rotating your compass 360 degrees––first in one direction, then the other–and making sure to maintain a slow and steady speed. The compass card should move through the fluid in its original orientation. If it seems to stick slightly before freeing itself and moving on, the unit needs to be repaired or replaced as necessary.

Now you need to check for damping. With the lubber's line aligned over one of the graduations and the compass card perfectly still, you want to pull the card off that graduation by 30 degrees using a magnet, screwdriver or other small piece of metal. Hold it there for at least 5 seconds, then remove the magnet or metal, placing it behind your back or sufficiently far away to negate the magnetic pull. The compass card should return to its original position. If it does not, if it is even 1.5 degrees distant from its starting point, or if the card sticks, you will need to repair or replace the compass as necessary.

Always err on the side of caution when deciding what to do about a suspected compass problem. This is a safety issue, not a cosmetic one.

– Linda Hoff