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18-3543 Outboard Thermostat for Johnson for Evinrude 6-250 HP V4 V6 Outboard Motors replaces 5005440 8330720 393659 434841 Sierra 18-3553
This is the outboard thermostat for Johnson Evinrude Outboard Models.
18-3543 Outboard Thermostat for Johnson for Evinrude 6-250 HP V4 V6 Outboard Motors replaces 5005440 8330720 393659 434841 Sierra 18-3553
Item #: 123513676

18-3543 Outboard Thermostat for Johnson for Evinrude 6-250 HP V4 V6 Outboard Motors replaces 5005440 8330720 393659 434841 Sierra 18-3553

Item #: 123513676

ETB 4065

Price Details

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This is the outboard thermostat for Johnson Evinrude Outboard Models.
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What Stands Out

High Compatibility
Designed to fit a wide range of Johnson and Evinrude outboard motors, ensuring hassle-free installation and operation across various engine models from 6-250 HP.
Durable Construction
Fabricated with high-quality materials to withstand harsh marine environments, ensuring long-lasting performance and reliability during extensive use in diverse boating conditions.
Efficient Cooling
Optimizes engine cooling performance, effectively preventing overheating and prolonging the engine's lifespan, thereby enhancing the overall boating experience and operational efficiency.

Product Details

Shop 18-3543 Outboard Thermostat for Johnson for Evinrude 6-250 HP V4 V6 Outboard Motors replaces 5005440 8330720 393659 434841 Sierra 18-3553 online at a best price in Ethiopia. B0D1MSWSY7
Engine Type4 Stroke
Mounting TypeTransom Mount
Fuel TypeGasoline
Maximum Horsepower250 Horsepower
Color18-3543
Material TypeAluminum
Brand NameGHmarine
ManufacturerGHmarine Parts Manufacturer
OEM Equivalent Part Number378065, 393659, 434841, 5005440, 8330720
Manufacturer Part Number18-3543
BrandGHmarine
MaterialAluminum
Item Weight0.5 lbs (230 grams)

Who Should Buy?

Suitable For
  • Boat Owners

    Ideal for boat owners with Johnson or Evinrude outboard motors needing reliable temperature regulation and efficient performance.

  • DIY Mechanics

    Great for DIY enthusiasts comfortable with basic maintenance who want to replace thermostats without professional assistance.

  • Fishing Enthusiasts

    Beneficial for fishing enthusiasts using higher HP outboards, ensuring optimal engine performance and reduced overheating risks.

Not Suitable For
  • Non-Johnson Users

    Not suitable for users with outboard motors from other brands needing specific thermostats for their engine types.

Product Description

18-3543 Outboard Thermostat for Johnson for Evinrude 6-250 HP V4 V6 Outboard Motors replaces 5005440 8330720 393659 434841 Sierra 18-3553

Have any Query? Chat with us

Customer Questions & Answers

  • Question: What is the purpose of the 18-3543 outboard thermostat?

    Answer: The 18-3543 outboard thermostat regulates the engine temperature in Johnson and Evinrude motors. By opening and closing at specific temperature thresholds, it plays a crucial role in preventing engine overheating while ensuring optimal performance. This thermostat is designed for 6-250 HP V4 and V6 motors, making it essential for maintaining engine health. Regular maintenance using a reliable thermostat like this one can prolong the lifespan of your outboard motor, ensuring you're always ready for a day on the water.
  • Question: How do I know if I need to replace my outboard thermostat?

    Answer: Signs that indicate a need for replacement include overheating engines, erratic temperature readings, or visible wear and corrosion on the thermostat. If your engine frequently runs hotter than normal or if you notice fluctuating temperature gauges, it may be time for a new thermostat. Additionally, during routine maintenance, checking for buildup or damages can help you decide if a replacement is necessary to keep your boating experience trouble-free.
  • Question: What models are compatible with the 18-3543 thermostat?

    Answer: The 18-3543 thermostat is specifically compatible with Johnson and Evinrude outboard motors ranging from 6 to 250 HP, including V4 and V6 configurations. It replaces several OEM part numbers such as 5005440, 8330720, 393659, and 434841, making it a versatile choice for many outboard users. Ensuring compatibility with your motor model is crucial for optimal performance, as the right thermostat will facilitate proper engine cooling and functioning.
  • Question: Can I install the 18-3543 thermostat myself?

    Answer: Yes, many boat owners opt to install the 18-3543 thermostat themselves, provided they have basic mechanical skills and tools. The installation process typically involves draining the cooling system, removing the old thermostat, cleaning the housing, and placing the new one in the correct orientation. However, refer to your boat’s service manual for specific instructions tailored to your engine model. Proper installation enhances performance and can prevent future overheating issues, ensuring a smooth ride on the water.
  • Question: What are the potential consequences of not replacing a faulty thermostat?

    Answer: Neglecting to replace a failing thermostat can lead to severe engine damage. An overheating engine can result in warped components, complete engine failure, or costly repairs. Even if the thermostat is merely sticking, you risk inefficient cooling, which can affect performance. It is vital to monitor engine temperature and replace faulty parts promptly to avoid expensive repairs and ensure the continued reliability of your outboard motor.
  • Question: How does the 18-3543 thermostat improve engine performance?

    Answer: By maintaining optimal engine temperatures, the 18-3543 thermostat ensures that the engine runs efficiently, preventing overheating and promoting longevity. This leads to better fuel economy and smoother operation. When temperatures are regulated properly, it allows for better combustion and reduces emissions, which is beneficial for both performance and the environment. Users can experience enhanced power output and responsiveness, making this thermostat a key component for any serious boater.
  • Question: Is the 18-3543 thermostat durable for marine use?

    Answer: Absolutely, the 18-3543 thermostat is specifically designed for marine applications. It is built from high-quality materials that resist corrosion and wear caused by harsh marine environments. This durability ensures reliable performance over prolonged use in freshwater or saltwater conditions. When equipped properly, the thermostat can withstand the rigors of various boating activities, making it a dependable choice for recreational or professional use.
  • Question: What should I do if I receive a defective thermostat?

    Answer: If you find that the 18-3543 thermostat is defective upon installation, it's important to stop using it immediately. Contact the supplier or retailer where you purchased it for assistance. Most suppliers will be able to guide you through their return process or exchange policies. Keeping the packaging and receipt can streamline this process. A faulty thermostat can lead to engine issues, so addressing it as soon as you notice any problems is crucial.
  • Question: What are the common symptoms of a malfunctioning outboard thermostat?

    Answer: Common symptoms of a malfunctioning thermostat include engine overheating, inconsistent temperature readings, and poor performance. Additionally, you might notice steam or excessive exhaust gases, which indicate temperature regulation issues. If you're experiencing any of these signs, promptly assessing the thermostat and considering a replacement can help you avoid more significant engine issues and maintain a good boating experience.
  • Question: Where can I buy the 18-3543 Outboard Thermostat?

    Answer: You can buy the 18-3543 Outboard Thermostat from Ubuy in Ethiopia. They offer a selection of marine parts, ensuring you find high-quality components for your outboard motors. With a straightforward purchasing process, Ubuy provides a reliable option for maintaining your Johnson and Evinrude motors. Whether you’re a weekend boater or a professional, having the right parts readily available is essential for smooth sailing.

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