My engine temperature slowly creeps up at idle and gets worse as I increase RPM. Whats wrong?
The most likely cause is a restriction in the sea water system. The best way to confirm a restriction is to measure the output of the sea water at the water outlet. Normally this is done at the wet exhaust elbow. Every system has a flow rate at a specified RPM, and measuring the water output (usually in gallons per minute) is the best way to check the entire system at one point. NOTE: It’s very difficult to make an assessment of water flow with a visual check. It may look like enough water flow when in fact there is a lack of flow. There are several points in the system that are subject to causing a restriction or poor flow. Start at the sea water inlet valve and follow the flow of water through the entire circuit checking for restrictions. Carefully examine hoses and fittings. Make sure you check the impeller and the condition of the pump body! The most common causes are a clogged sea water strainer, a dirty heat exchanger or a clogged water injection fitting on the wet exhaust elbow.
