Heat exchanger conversion kits

Cooling systems for marine engines

Many older marine engines are directly cooled with outside water (seawater). Although this system is simple, it can lead to limescale, salt buildup, and corrosion in the engine block over time. This can clog cooling channels, and eventually, the engine may overheat.

With a heat exchanger cooling system, a marine engine can be converted to indirect cooling with coolant. In this system, coolant circulates through the engine block, while outside water only flows through the heat exchanger to dissipate the heat. This way, the seawater no longer comes into direct contact with the engine block, which can significantly extend the engine’s lifespan.

Find universal cooling system kits here: 17pk, 25pk, 40pk and 450pk and parts of the Martec cooling system.

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Conversion from direct to indirect cooling

Converting a marine engine to a closed cooling system is typically done with a complete heat exchanger kit. Such a kit often consists of:

  • Heat exchanger
  • Expansion tank
  • Thermostat housing or adapter
  • Hoses and fittings
  • Mounting brackets

With these components, a closed cooling circuit with coolant is created, while outside water only cools the heat exchanger.

  • This system has several advantages:
  • Less corrosion in the engine block
  • Higher and more stable operating temperature
  • Better engine efficiency
  • Winter resistance with antifreeze
  • Easier maintenance