Ignoring Whining Now Could Make You Cry Later
Some problem noises are obvious. Some are not. Get into the habit of regularly listening to critical components such as the fresh- and raw-water pumps, alternator, transmission, injector pump (if you have a diesel), and any other convenient spots.
- A gravelly noise from a component with bearings can indicate that the bearings are about to fail. The alternator and fresh-water recirculating pump are prime suspects when you hear this. A belt that's too tight could hasten either of these failures.
- Change in tilt-lift motor noise on an outboard could be a precursor to pump failure or air in the tilt motor fluid. It could also indicate drop in voltage that could indicate fault in the charging system, corroding connections, or wiring. Note: It's normal for most tilt motors to have two different levels of sounds as the function shifts from power trim adjustment to full tilt.
- Variation in the engine noise, called "hunting," could indicate impurities in the fuel, an air leak in the suction line, a clogging filter, a failing fuel pump, or a failing injector pump.
- A "thunk" when you push the starting button means problems, even if your engine then seems to start normally. The "thunk" could be caused by a hydraulic lock resulting from water standing on top of a piston. If you hear a lighter "clunk" in the starter, it may be a bad solenoid, engagement gear, or starter.
- A squealing noise could indicate a loose V-belt, but it could also be a clue that one of the components it is turning, such as the alternator or fresh-water recirculating pump, is freezing up. Bad bearings could be causing this in both components. Overload or deteriorating internal parts could cause this in the alternator.
- Unusual cracking or creaking sounds when hitting seas, running at speed, or otherwise stressing the hull could indicate delamination, structural bonds failing between bulkheads or supports, impending transom detachment, or other serious problems.
- The bilge pump running more often than usual means you should start looking for a leak. Some less obvious sources of water in the bilge include the propeller shaft seal, the freshwater system, the cooling system, the pop-off valve in the hot water heater, and the hoses on the engine.
- Unusual noises in the transmission usually signal a problem developing that could require professional help very soon.