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Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
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Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
Durable construction, providing reliable performance and long service life.
Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree
Item #: 123994506

Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree

Item #: 123994506

BDT 3268

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What Stands Out

Precision Temperature Control
This thermostat kit offers precise control over engine temperatures, ensuring optimal performance and longevity for Mercury and Mercruiser engines. It effectively prevents overheating, enhancing reliability on the water.
Direct Replacement
Designed to perfectly replace Sierra part numbers 18-3650, 18-3550, 59078Q3, and 59078T3, this kit simplifies installation, making it a hassle-free solution for boat owners looking to upgrade their cooling systems.
Durable Construction
Made with high-quality materials, the thermostat kit guarantees durability and long-lasting service, providing exceptional value by reducing the frequency of replacements and maintaining engine efficiency in demanding conditions.

Product Details

Shop Thermostat Kit Replaces Sierra 18-3650 18-3550 59078Q3 59078T3 Replacement for Mercury/Mercruise 140 Degree online at a best price in Bangladesh. B0BWHC95G7
  • Aftermarket thermostat.replaces GLM 13370; Mallory 9-43153
  • Package includes 1 x Thermostat,1 x Thermostat Cover Gasket
  • 140°F degree thermostat
  • Durable Construction,providing reliable performance and long service life
  • Fits 1998 & older MCM GM in-line 4 & 6 cyl. Engines

Product Technical Details

Manufacturer‎BOLEWIN
Brand‎BOLEWIN
Model‎Thermostat
Item Weight‎1.44 ounces
Package Dimensions‎4.69 x 3.15 x 1.34 inches
Item model number‎18-3650
Exterior‎Chrome
Manufacturer Part Number‎18-3650

What's in the box

Thermostat

Who Should Buy?

Suitable For
  • Boat Owners

    Ideal for boat owners needing to replace their Mercury/Mercruise thermostats for improved engine cooling performance.

  • DIY Enthusiasts

    Perfect for do-it-yourselfers who want to perform engine maintenance without professional help using this cost-effective kit.

  • Maintenance Services

    Suitable for marine maintenance services looking for reliable replacement parts to offer customers for engine thermoregulation.

Not Suitable For
  • Non-Marine Users

    Not suitable for users who do not operate boats or marine engines where this thermostat type is required.

Product Description

Have any Query? Chat with us

Customer Questions & Answers

  • Question: What are the compatibility details of the Thermostat Kit that replaces Sierra 18-3650?

    Answer: The Thermostat Kit is designed to replace specific models including Sierra 18-3650, 18-3550, 59078Q3, and 59078T3. This compatibility ensures that it fits seamlessly into various Mercury and Mercruiser engines, maintaining optimal cooling performance. If you own a boat or watercraft with these engines, this replacement kit is a reliable solution for overheating issues, helping prolong engine life and performance.
  • Question: How can I install the Thermostat Kit Replacing Sierra models?

    Answer: Installation of the Thermostat Kit requires basic mechanical skills and tools. Start by locating the thermostat housing in your engine. After draining the cooling system, remove the housing to access the old thermostat. Replace it with the new kit, ensuring proper gasket alignment. Reassemble and refill the cooling system. Correct installation is crucial as it ensures effective temperature control, preventing overheating during operation when you are on the water.
  • Question: What temperature does the Thermostat Kit maintain?

    Answer: This Thermostat Kit operates at a consistent 140 degrees, making it ideal for maintaining optimal engine temperature in both freshwater and saltwater applications. By ensuring the engine runs within this temperature range, you can achieve better fuel efficiency and performance, especially in demanding conditions like high speeds or heavy loads when out on the lake or ocean.
  • Question: What type of engines can benefit from this Thermostat Kit?

    Answer: The Thermostat Kit is particularly suitable for Mercury and Mercruiser engines that utilize the part numbers Sierra 18-3650, 18-3550, 59078Q3, and 59078T3. It's designed to enhance cooling efficiency, making it an essential part for maintaining robust performance in recreational boats, fishing vessels, and high-performance watercraft where engine reliability is paramount.
  • Question: Is this kit made from durable materials?

    Answer: Yes, the Thermostat Kit is constructed from high-quality, corrosion-resistant materials that can withstand extreme engine conditions. Enhanced durability is crucial for components exposed to harsh marine environments, ensuring longevity and reliability. This durability ensures that your boat remains operational and efficient during extended outings, negating the need for frequent replacements.
  • Question: How will I know when to replace my thermostat?

    Answer: Common signs that indicate the need for a thermostat replacement include overheating engines, fluctuating temperature readings, or visible leaks around the thermostat housing. Regular monitoring of the engine's temperature gauge during use can help identify these issues early. Addressing thermostat problems promptly can prevent more severe engine damage, ensuring that your boating experience remains enjoyable and trouble-free.
  • Question: Can this replacement kit improve engine performance?

    Answer: Indeed, by maintaining an optimal operating temperature of 140 degrees, the Thermostat Kit can enhance overall engine performance. Proper thermal regulation prevents overheating, which can lead to engine wear and inefficiency. As a result, aspects such as fuel consumption and emissions may improve, making your boating experience smoother and more environmentally friendly.
  • Question: What tools will I need for the installation of this kit?

    Answer: To install the Thermostat Kit, you will typically need basic hand tools such as a socket set, wrenches, screwdrivers, and a gasket scraper if the old gasket needs removing. Having a torque wrench may also be beneficial for securing the housing. Preparing the right tools ensures a smoother installation process and minimizes the risk of damaging components, allowing you to focus on enjoying your time on the water.
  • Question: Where can I buy the Thermostat Kit Replaces Sierra models?

    Answer: You can purchase the Thermostat Kit that replaces Sierra 18-3650, 18-3550, 59078Q3, and 59078T3 from Ubuy in Bangladesh. Ubuy offers a convenient platform for finding various automotive and marine parts, providing detailed product descriptions and reliable service to assist you in securing the right components for your needs.
  • Question: Is there any specific maintenance required for this Thermostat Kit?

    Answer: While the Thermostat Kit does not require extensive maintenance, regular checks on engine temperature and any signs of leaks are advisable. It's also a good practice to inspect the coolant level and condition to ensure optimal performance. Maintaining these aspects can prevent potential overheating issues, thereby extending the life of both the thermostat and the engine itself while you're enjoying your cruises.

BOLEWIN Thermostats ‎18-3650 Editorial Review

**** The Thermostat Kit designed to replace Sierra models 18-3650, 18-3550, and 59078Q3 offers a mixed but generally positive customer experience. Many users have found the product to fit well and function as intended. Feedback highlights that installation is straightforward and the performance meets expectations, with some customers reporting that the thermostat works effectively for various marine applications, including for OMc Cobra engines from 1986 to 1993. However, not all experiences have been positive. One customer reported a significant issue with the unit breaking within just an hour of use, leading to a return. This suggests some inConsistency in product durability, which may be a concern for potential buyers looking for reliability in performance. Overall, while many customers appreciate the functionality and fit of the thermostat replacement kit, the possibility of defects does warrant caution. **

Customer Reviews & Ratings

4.2
28 customers ratings
  • 5 Star
    68%
  • 4 Star
    11%
  • 3 Star
    10%
  • 2 Star
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  • 1 Star
    11%

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Pros

  • Fits as described
  • Generally functions well after installation
  • Effective for specific marine engine models

Cons

  • Reports of early failure within the first hour of use

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BDT 3268

Order now and get it around Friday, August 21

QTY:

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Our Top Logistics Partners
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Features & Benefits

  • Replaces multiple models including Sierra and Mercury.
  • Includes thermostat and gasket for easy installation.
  • Designed for 1998 & older MCM GM in-line 4 & 6 cyl. Engines.
  • Operates at a reliable 140°F degree.
  • Constructed for durability and longevity.
  • Perfect for maintaining optimal engine performance.

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