I have milky coloured oil, what's it mean?
Many people jump to the worst scenario of cylinder head or cracked block when water is found in the oil. The water becomes emulsified with the oil when the engine is run to temperature and goes white / creamy in colour. You will also notice the oil level rising on the dipstick.
On a boat this can in fact be quite a simple problem to solve. The chances are that it is simply the seals on the water pump which have gone. The pump is driven from the engine, water is pulled up from the river, if the seal separating the two is worn or damaged water can enter the engine.
If it is caught in time it is simply a matter of changing the water pump seals and then changing the oil and oil filter a couple of times to clear any emulsified oil. Pump seals and spares are generally available from the Freeman Shop.
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