It may sound like a bad thing, but it’s not. You can run a Mercury outboard out of water by using flushing muffs or a flushing port. We’ll go over each method of how to run a mercury outboard out of water in more detail below.
Why run a Mercury outboard out of water?
Flushing an outboard motor is an important maintenance procedure that helps keep the engine clean, prevent corrosion, and ensure optimal performance. Here are some reasons why flushing an outboard motor is necessary:
Salt and Mineral Removal: If you operate your outboard motor in saltwater or brackish water, flushing is crucial to remove salt, minerals, and other contaminants from the cooling system. Saltwater is corrosive, and if left in the engine, it can cause damage and corrosion to various components. Flushing helps flush out these harmful substances, preventing corrosion and maintaining the engine’s health.
Debris and Sediment Removal: Flushing also helps remove debris, marine growth, sand, or other particles that may have entered the cooling system. These contaminants can block water passages, impede water flow, and lead to overheating. Flushing helps clear out these blockages, ensuring adequate cooling and preventing potential engine damage.
Cooling System Maintenance: The cooling system of an outboard motor is responsible for regulating the engine’s temperature. Flushing the motor helps maintain the efficiency of the cooling system by keeping it free from obstructions. A clean cooling system ensures proper heat dissipation and prevents overheating, which can lead to engine damage and reduced performance.
Winterization: Flushing is an essential step in the winterization process. Before storing the outboard motor for an extended period, flushing helps remove any accumulated salt, debris, or contaminants. By flushing the engine, you minimize the risk of corrosion and ensure the motor is prepared for storage during the off-season.
Performance and Longevity: Regularly flushing your outboard motor contributes to its overall performance and longevity. By preventing corrosion, removing contaminants, and maintaining a clean cooling system, you help preserve the engine’s efficiency, power, and lifespan.
It’s important to note that the specific flushing requirements and procedures may vary depending on the outboard motor manufacturer and model. Always refer to the manufacturer’s guidelines and instructions for the recommended flushing methods, duration, and frequency
What to use to run a Mercury outboard out of water
Flush Muffs: Flush muffs are devices designed to simulate water flow while running an outboard motor out of water. They typically consist of rubber cups that fit over the water intake ports on the lower unit of the outboard. You attach a garden hose to the flush muffs, allowing water to flow into the rubber cups and through the cooling system. This method provides some cooling to the engine, but it’s important to note that it doesn’t replicate the exact conditions of running the motor in water.
Portable Water Tank: Another option is to use a portable water tank or barrel filled with water. You can place the outboard motor’s lower unit into the water, ensuring that the water intake ports are submerged. With the motor in the water, you can start it and run it for a short period of time. This method provides better cooling than flush muffs but still doesn’t fully replicate the conditions of running the motor in the water.
Is it safe to run an outboard with muffs?
Yes, it is safe to run an outboard with muffs on it. Just make sure the motor has water going into the intake and coming out the pee hole up top.
How long to flush a Mercury outboard motor
When flushing an outboard motor, the duration of the flushing process can vary depending on the specific motor and the reason for flushing. Here are some general guidelines to follow:
Routine Flushing: For regular maintenance and flushing after each use in saltwater or brackish water, a general rule of thumb is to flush the outboard for approximately 5 to 10 minutes. This timeframe allows for the engine to be adequately cooled and for any salt or debris to be flushed out of the cooling system.
Heavy Contamination: If the outboard has been exposed to heavy contamination or excessive saltwater use, you may want to flush it for a longer period. Flushing for 15 to 20 minutes can help ensure thorough cleaning of the cooling system.
Winterization: When preparing the outboard motor for storage during winter or extended periods of inactivity, it’s recommended to flush the motor for a longer duration, usually around 20 to 30 minutes. This extended flushing helps remove any accumulated salt or deposits that could potentially cause corrosion or other issues during the storage period.
Always refer to the manufacturer’s instructions and guidelines specific to your outboard motor for the recommended flushing duration. Additionally, it’s important to use proper flushing attachments, such as flush muffs or dedicated flushing devices, to ensure water flow through the cooling system is adequate.
What are flushing muffs?
Flushing muffs, also known as flush muffs or earmuffs, are devices used to flush an outboard motor’s cooling system with freshwater while the motor is running outside of water. They are commonly used for maintenance, winterization, or troubleshooting purposes. Flushing muffs are designed to simulate the water flow that would normally occur when the outboard is submerged in a body of water.
Flushing muffs typically consist of two rubber cups or muffs that fit over the water intake ports on the lower unit of the outboard motor. These cups are connected by a strap or clamps to hold them securely in place. One end of the flushing muffs has hose attachments to connect a freshwater source, such as a garden hose.
How to run a Mercury outboard out of water with flushing muffs
- Ensure the outboard motor is turned off and not running.
- Position the flushing muffs over the water intake ports on the lower unit of the outboard, ensuring a secure fit.
- Attach a garden hose to the hose attachment on the flushing muffs.
- Turn on the freshwater source, allowing water to flow through the garden hose and into the flushing muffs.
- Start the outboard motor according to the manufacturer’s instructions.
- Let the motor run for the recommended flushing duration, typically 5 to 10 minutes or as specified by the manufacturer.
Flushing muffs allow freshwater to circulate through the outboard motor’s cooling system, helping to remove salt, debris, and contaminants. However, it’s important to note that running an outboard motor with flushing muffs does not replicate the exact conditions of running the motor in water. Therefore, it’s best to limit the duration of running the outboard with flushing muffs and not use it as a substitute for running the motor in an actual water source whenever possible.
What happens if I don’t flush my Mercury outboard regularly?
If you neglect to flush your outboard motor regularly, especially after use in saltwater or brackish water, several potential issues can arise:
Corrosion: Flushing the outboard motor helps remove salt, minerals, and other contaminants from the cooling system. Without proper flushing, these substances can build up over time and lead to corrosion within the engine. Corrosion can cause damage to various components, including the cooling passages, cylinder heads, and internal parts, reducing the engine’s performance and lifespan.
Blockages: Debris and marine growth, such as seaweed or sand, can accumulate in the cooling system if not flushed regularly. These blockages restrict water flow and impede the engine’s ability to cool properly. Overheating is a common consequence of blockages, which can result in engine damage, reduced power, and potentially even engine failure.
Impeller Damage: The impeller is responsible for drawing water into the outboard motor’s cooling system. If the engine is not flushed regularly, debris or sediment can enter the system and damage the impeller. A damaged or worn impeller can lead to reduced water flow, inadequate cooling, and potential overheating issues.
Performance Degradation: Over time, the accumulation of contaminants in the cooling system can affect the outboard motor’s overall performance. The engine may struggle to achieve optimal power, experience reduced fuel efficiency, or exhibit irregular running. Neglecting to flush the motor can contribute to these performance issues.
Reduced Lifespan: The combined effects of corrosion, blockages, impeller damage, and performance degradation can significantly shorten the lifespan of your outboard motor. Regular flushing helps maintain the engine’s health and prolong its longevity.
To ensure the longevity and reliable operation of your outboard motor, it is essential to follow the manufacturer’s recommendations for flushing, particularly after use in saltwater or brackish water. Regular maintenance, including flushing, is crucial for preserving the performance and durability of your outboard motor.
Can you run a Mercury outboard on the flush port?
Most Mercury outboards come equipped with a built-in flush port that allows you to simply attach a garden hose and flush it out. Stokes suggests flushing it for at least 15 minutes. With the Mercury system, there’s no need to run the engine to flush it. The flush port could be on the top or the side of the outboard depending on your Mercury model. The new Mercury outboards do not need lower unit flushing with the top flushing attachment.