© 2011 Brian L Johnson Avoiding weed problems As we have learnt to our cost, weeds can be a problem when cruising. This is because the engine sucks up river water and runs it through a radiator to cool the engine. That heated river water is then squirted out into the exhaust pipe to cool it and reduce the noise. Even though the river water inlet hole is small, it is still possible to draw in little bits of weed and these can clump together and choke the pipes. If the pipes get blocked, the engine can’t get any water to cool itself and will overheat. As the engine gets hotter, the first thing to suffer will be the rubber blades inside the water pump. They start to melt and disintegrate and then the engine will overheat very quickly. To avoid the problem, some suggestions: 1. Cruise in the middle of narrow and weed filled rivers when possible 2. Take care about ‘gunning’ the throttle – this could suck in weed, it is best to manoeuvre or turn slowly using forward, neutral and reverse and low throttle (it is in fact possible to turn the boat in almost its own length this way) 3. The most dangerous time for weed intake is probably mooring and unmooring – try to develop a technique where you moor very slowly, the crew member steps off and stops the boat with the rope, saving the need to use the throttle/reverse to any extent. When unmooring it may be worthwhile to have the crew member push the stern out using the boathook and then gently reversing out – hopefully avoiding weed near the bank. See the next page for how to change the weedtrap filter.