Outboard motors are widely used in the marine industry for powering small to medium-sized boats. These engines provide great functionality, reliability, and efficiency. However, like any mechanical device, they require proper maintenance and monitoring to ensure their optimal performance. One essential aspect of an outboard motor’s health is its cooling system, specifically the water pump.
The water pump in an outboard motor plays a critical role in keeping the engine cool by circulating water through the powerhead to dissipate heat. A telltale sign that your water pump is functioning correctly is a steady stream of water, also known as “spitting water,” that exits the engine. In this blog post, we’ll discuss the factors affecting when an outboard spits water, how to diagnose potential issues, and how to resolve them with preventative maintenance and repair.
Understanding the Cooling System of an Outboard Motor
Before delving into the specifics of outboard motors spitting water, it’s crucial to understand the basics of their cooling system. The primary components of this system include:
1. Water Intake
Located on the lower unit, the water intake is a series of small openings where water is drawn into the engine. This water is used to cool down the engine during operation.
2. Water Pump
The water pump, also located in the lower unit, is responsible for circulating water through the engine. It uses an impeller, which is a rubber wheel with flexible blades that spin and create suction to draw water from the intake.
3. Thermostat
The thermostat is a temperature-sensitive valve that regulates the flow of water through the powerhead. When the engine is cold, the thermostat remains closed, allowing the engine to warm up quickly. Once the engine reaches its optimal temperature, the thermostat opens to let water flow through and dissipate heat.
4. Water Passage
This is the pathway the water takes through the engine. It circulates from the water pump, through the powerhead, and out of the engine through the “tell-tale” or “pee hole,” commonly visible as the outboard spitting water.
Factors Affecting When an Outboard Spits Water
While it’s common to see water exiting the engine during operation, several factors can affect the time it takes for your outboard motor to start spitting water. These include:
1. Engine Temperature
When an outboard is first started, the thermostat often remains closed to allow the engine to reach its ideal operating temperature. As a result, it might take some time before water flow is visible.
2. Water Pump Condition
The efficiency and effectiveness of your water pump play a significant role in determining when an outboard starts spitting water. A worn, damaged, or dirty impeller can result in reduced water flow or delayed water circulation.
3. Debris and Obstructions
The presence of debris in the water intake or water passages can also impact water circulation. In some cases, obstructions may prevent water from being pumped through the engine entirely.
Identifying Issues with Outboard Water Flow
If you notice that your outboard motor is not spitting water or has a significantly reduced flow, you should take immediate action to prevent overheating and engine damage. The following steps can help you diagnose issues with water circulation:
1. Visually Inspect Water Intakes
Inspect the water intakes for any visible obstructions, such as weeds or debris. Remove any blockages and check the water flow once more.
2. Check the Thermostat
If the engine is cold, it might take longer for water to start spitting due to the closed thermostat. Monitor the engine temperature and allow it to run for a few minutes before checking for water flow.
3. Inspect the Telltale
Clogged or blocked “tell-tales” can cause a reduced or nonexistent water stream. Inspect the telltale and use a small wire or compressed air to clear any obstructions if necessary.
4. Evaluate Water Pump and Impeller Condition
If the previous steps do not resolve the issue, inspect the water pump and impeller for wear or damage. This inspection may involve removing the lower unit and disassembling the water pump housing.
Preventative Maintenance and Repairs
To ensure the longevity and optimal performance of your outboard motor, it’s crucial to perform regular maintenance and address any issues promptly. Essential steps include:
1. Flush Your Outboard After Each Use
Flushing your outboard with fresh water after each use helps remove salt, sand, and other debris from the water passages and cooling system.
2. Regularly Inspect the Water Pump and Impeller
Inspect the water pump and impeller every 100 hours of operation or at least once a year. Replace any worn or damaged components as needed.
3. Clean the Thermostat and Replace As Needed
Regularly clean the thermostat housing and internal components. Replace the thermostat if it’s not opening or closing properly, or if it’s older than 3-4 years.
4. Keep the Water Intakes Clear
Regularly check and clean the water intakes to ensure optimal water flow. Be sure to remove any weeds or debris that may become lodged in the intakes during operation.
By following these maintenance steps and addressing any issues as soon as they arise, you can prevent engine damage and ensure your outboard motor continues to spit water at the appropriate time, keeping your engine cool and running smoothly for years to come.
Frequently Asked Questions
How long does it take for water to come out of an outboard motor?
Water should start coming out of the outboard motor within 15-30 seconds after the engine has been started. If it takes longer than that, there may be an issue with the cooling system or water pump.
Why is my outboard not spitting water?
There could be numerous reasons why your outboard is not spitting water, such as a clogged water intake, a damaged or worn-out impeller, a faulty water pump, or a problem with the thermostat. It is important to address this issue in order to avoid overheating and damage to the engine.
Does water come out of exhaust on outboard motor?
Yes, a small amount of water may come out of the exhaust on an outboard motor. This is normal and indicates that the cooling system is functioning properly. However, excessive water coming out of the exhaust may be a sign of a problem, such as a cracked exhaust manifold or a blown head gasket.
Should the water coming out of my outboard be cold?
No, the water coming out of your outboard motor should be warm or even hot. This is because the water serves to cool down the engine, absorbing heat as it passes through the cooling system. If the water is cold, it may indicate a problem with the cooling system, such as a blockage or a malfunctioning thermostat.
How can I check if my outboard motor is pumping water effectively?
You can check the water flow from the tell-tale hole, a small hole typically found in the lower unit of the motor. When the engine is running, you should see a steady stream of water coming out of this hole, which indicates that the water pump is working properly.
What should I do if my outboard motor is overheating?
If your outboard motor is overheating, it is important to shut it off immediately to prevent damage to the engine. Check for any noticeable issues in the cooling system, such as clogged water intakes, a damaged impeller, or a faulty thermostat. It is recommended to consult a professional to properly diagnose and repair the issue.
How often should I replace the impeller on my outboard motor?
The impeller is a crucial component of the cooling system and should be replaced every two to three years, or more often if it shows signs of wear or damage. Regular replacement ensures that your outboard motor stays cool and runs efficiently.
Can I run my outboard motor without cooling water?
Running an outboard motor without cooling water can quickly lead to overheating, causing damage to the engine and the potential for costly repairs. Always ensure that the motor is being properly cooled before starting it, either by submerging the lower unit in water or connecting a water supply using a flushing device or earmuffs.
What is the purpose of a thermostat in an outboard motor?
The thermostat in an outboard motor is responsible for regulating the flow of cooling water through the engine. It maintains the engine’s operating temperature within an optimal range, ensuring efficient performance and preventing overheating. A malfunctioning thermostat can cause the engine to run too cold or too hot, leading to decreased performance and potential damage.
Can I use my outboard motor in salt water?
Yes, many outboard motors are designed to be used in both fresh and salt water. However, it is essential to thoroughly flush the cooling system with fresh water after each use in salt water to prevent corrosion and buildup in the cooling passages. Consult your owner’s manual for specific instructions on how to properly maintain your outboard motor in saltwater conditions.
