IMPULSOR

Function and technical context

The impeller is the central component of the outboard or inboard engine's water pump, responsible for circulating cooling water through the engine block. Made of high-resistance vulcanized rubber, its flexible vanes generate the necessary flow to maintain the working temperature within safe ranges. An impeller in poor condition drastically reduces coolant flow, causing engine overheating, damage to head gaskets and, in the most serious cases, impeller seizure. It is installed in the water pump housing, usually located at the bottom of the foot or in the transfer case, and works in direct contact with sea or river water, which accelerates its wear due to abrasion and fatigue of the elastomer.

When to replace this part?

The most common symptoms of a worn impeller are the reduction or absence of the cooling water jet through the bilge pilot, active temperature alarm and loss of power associated with overheating. Broken or deformed vanes can also circulate through the refrigeration circuit and clog the thermostat or other ducts. It is recommended to replace the impeller every 200-300 hours of navigation or, at least, every two seasons of use, regardless of its external appearance. Changing it preventively at each seasonal inspection avoids serious breakdowns at sea where a repair can be inaccessible and extremely expensive.

Engine Compatibility

Equivalent manufacturer part numbers