Raw water failure is the most common problem with marine diesel engines. Within a short period of time expensive damage to the engine or wet exhaust system can occur. Reduction or total blockage of the raw water flow could be caused by debris in the inlet through-hull, a clogged inlet strainer or failure to open the inlet seacock.
The raw seawater cooling flow takes the heat from the engine cooling water in the heat exchanger and discharges it via the exhaust system. Failure of this flow of raw water will not only lead to overheating of the engine but also overheating of the exhaust system components. And it can occur before the normal engine block mounted temperature sensor detects it.
If the wet exhaust muffler melts, the raw water pump will continue to pump water into the boat, creating another problem to contend with.
Sentry™ provides an audio and visual alarm if your engine’s raw water cooling flow should be interrupted. Simple to install, a Sentry exhaust temperature alarm makes good sense. That’s why they’re used by fishing boats in Alaska, tugs in the Panama Canal and pleasure boats everywhere.
