An important part of Radio Control Electric boating is keeping the equipment cool. Both the ESC and motor require water cooling in most cases in order to keep temperatures low.
It is recommended to keep motor and ESC temperatures below 140F or 60C. This will ensure the components will not fail by excessive temperature.
How the Water Cooling system works
In a Radio Control Boat, water is forced through the water cooling system. Water is picked up through the rudder most commonly, or an externally mounted pickup typically located on the transom. Water is transferred through the cooling system by means of silicon tubing. This tubing is typically used for fuel delivery in RC Nitro vehicles. Its flexibility works very well for routing the cooling water through the boat. The first component to receive water is recommended to be the ESC, although not required to be. Reasoning behind this, is to provide the coldest water here first as the motor generally produces or expels more waste heat.
Once the water is routed in to the ESC, another silicon line can be used to go from the ESC to the motor. The exit from the motor can lastly be routed to a water exit. The best location for a water exit is best to be on the port or left hand side of the hull. This is the best location if you are a racer or even sport boater. As laps are made in a clockwise direction the water exit will be easily seen on shore to be certain there is adequate flow.
Water Cooling Installation
Water Cooling in Radio Control Electric boats is actually quite easy. Most motors have aftermarket water cooling jackets available. Silicon type slide on with ease while others take a slightly different approach to install. For added cooling efficiency it may be a good idea to try and make the input water to the jacket on the bottom and the output water on the top. This will allow any air in the system to filter up and exit out the output water nipple.
All boat ESC’s made specifically for RC boats will have the plumbing already available to hook up. If your ESC has 2 sets of cooling paths, be certain to run a small section of tubing between them.
It’s important to not kink or have any obstruction to the water cooling system. It is ideal to have the best most free flowing system as possible. A common myth for water cooling on an Electric boat, is ensuring the water has enough time to heat soak. This is not true. It is best to have the most free flowing output of water as the water cooling system will allow.