Most of us on I.W. have been running model boats for quite a while. But there are plenty of inexperienced boaters as well.
Properly cooling your engine is a good subject to discuss for new boaters.
Back when I got started we made our own rudders, silver soldering a steel blade to a steel post. We used a brass tube to scoop water behind the prop and then used a silicone tube to take water from the scoop to the engine water-cooled head. A water fitting carried the cooling water from the engine to outside the hull. From the shore, we could see water squirting out of this fitting to make sure our engine was cooled.
An enterprising person came up with an aluminum, wedge shaped rudder with a built in water scoop. Almost everyone today is using a rudder with the built in water scoop. Water is directed from the rudder to the engine's water jacket.
Your engine builds heat by burning fuel. It creates a lot of heat. The heat is created between the head button and piston face. This is the hottest area in the engine. If this area gets too hot, engine performance drops and sometimes the piston is ruined.
Most of the heat generated escapes through the exhaust. But, the area between the head button and piston face still need cooling. The crankcase does not get overheated as it is removed from the combustion area and cooling fuel is directed into the crankcase. The area you need to cool is the upper end of the engine. Most engines have either air cooling fins or a water jacket around the head button.
The water scoop will send more water to the water jacket than is necessary. The brass water fittings will allow more water into the water jacket than is necessary. As a result, many new boaters over cool their engines.
Our engines need heat to burn nitro fuel The higher the nitro content, the more heat is needed. If your engine is too cool, it will not burn all of the nitro. That is when expensive nitro is wasted, going out with the exhaust.
To prevent your engine from becoming overcooled you can restrict the water flow. Experienced model boaters use different methods to restrict water flow. Some use a small plastic tie-wrap on the silicone water line. The tighter the wrap, the less water gets to the water jacket. Some use a needle valve in the silicone water line to adjust water flow. Some remove one brass water jacket fitting, seal the hole off with a set screw, then drill a small hole in the water jacket top to allow water to flow at a reduced rate.
This leads to the questions, how cool is too cool? And, how hot is too hot? Some boaters actually use a heat gun to monitor the engine heat, adjusting the water needle valve to get the exact temperature they want. I feel the water jacket when my boats come back in. The water jacket should be cool enough for me to hold without burning myself, but hot enough that I can't hold it more than several seconds.
The engines we buy, produced in Europe, are designed for a lot more cooling than we need in North America and Australia. This is to suit the European market. Their most popular classes are 30 minute endurance events with a completely cowled engine and pipe. In this instance, the engine needs much more cooling. Our 3 to 4 minute races, even with a cowled engine, do not produce as much heat as in the European endurance races.
Check your water jacket temperatures often as the water we run in can change temperature during the days you are running.
Properly cooling your engine is a good subject to discuss for new boaters.
Back when I got started we made our own rudders, silver soldering a steel blade to a steel post. We used a brass tube to scoop water behind the prop and then used a silicone tube to take water from the scoop to the engine water-cooled head. A water fitting carried the cooling water from the engine to outside the hull. From the shore, we could see water squirting out of this fitting to make sure our engine was cooled.
An enterprising person came up with an aluminum, wedge shaped rudder with a built in water scoop. Almost everyone today is using a rudder with the built in water scoop. Water is directed from the rudder to the engine's water jacket.
Your engine builds heat by burning fuel. It creates a lot of heat. The heat is created between the head button and piston face. This is the hottest area in the engine. If this area gets too hot, engine performance drops and sometimes the piston is ruined.
Most of the heat generated escapes through the exhaust. But, the area between the head button and piston face still need cooling. The crankcase does not get overheated as it is removed from the combustion area and cooling fuel is directed into the crankcase. The area you need to cool is the upper end of the engine. Most engines have either air cooling fins or a water jacket around the head button.
The water scoop will send more water to the water jacket than is necessary. The brass water fittings will allow more water into the water jacket than is necessary. As a result, many new boaters over cool their engines.
Our engines need heat to burn nitro fuel The higher the nitro content, the more heat is needed. If your engine is too cool, it will not burn all of the nitro. That is when expensive nitro is wasted, going out with the exhaust.
To prevent your engine from becoming overcooled you can restrict the water flow. Experienced model boaters use different methods to restrict water flow. Some use a small plastic tie-wrap on the silicone water line. The tighter the wrap, the less water gets to the water jacket. Some use a needle valve in the silicone water line to adjust water flow. Some remove one brass water jacket fitting, seal the hole off with a set screw, then drill a small hole in the water jacket top to allow water to flow at a reduced rate.
This leads to the questions, how cool is too cool? And, how hot is too hot? Some boaters actually use a heat gun to monitor the engine heat, adjusting the water needle valve to get the exact temperature they want. I feel the water jacket when my boats come back in. The water jacket should be cool enough for me to hold without burning myself, but hot enough that I can't hold it more than several seconds.
The engines we buy, produced in Europe, are designed for a lot more cooling than we need in North America and Australia. This is to suit the European market. Their most popular classes are 30 minute endurance events with a completely cowled engine and pipe. In this instance, the engine needs much more cooling. Our 3 to 4 minute races, even with a cowled engine, do not produce as much heat as in the European endurance races.
Check your water jacket temperatures often as the water we run in can change temperature during the days you are running.
