SIERRA 18-3550 Thermostat Md I/o 140D

( Brand: Sierra ), ( Manufacturer Part Number: 18-3550 ), ( Part Type: Thermostat ), ( Unit Of Measurement: Ea )

Review SIERRA Thermostat I/o Md fits MERCRUISER

The Sierra 18-3550 Mercruiser Thermostat is a crucial component in the cooling system of your marine engine, specifically designed for MerCruiser engines with I/O (Inboard/Outboard) configurations. This thermostat, with part number 59078 MD, is manufactured by Sierra, a trusted name in the marine industry known for its high-performance cooling solutions.

This thermostat is engineered to maintain optimal engine operating temperature, ensuring efficient and reliable engine performance. It features a 140 F (60 C) temperature rating, which is ideal for marine applications where engine temperatures can vary significantly. The thermostat is constructed from premium materials, including a durable stainless steel housing, to withstand the harsh marine environment.

The Sierra 18-3550 Mercruiser Thermostat is designed to provide accurate temperature control by opening and closing the cooling circuit based on engine temperature. The thermostat uses a mechanical design, which offers a proven, dependable solution for temperature regulation. The thermostat's opening temperature is preset at 140 F, and it maintains this temperature by closing the cooling circuit when the engine reaches this temperature.

Installing the Sierra 18-3550 Mercruiser Thermostat is a straightforward process. It is compatible with various MerCruiser engines, including those with I/O configurations. The thermostat comes with all necessary mounting hardware, ensuring a hassle-free installation experience.

In summary, the Sierra 18-3550 Mercruiser Thermostat is a vital component for maintaining optimal engine temperature in your marine application. Its durable construction, accurate temperature control, and compatibility with various MerCruiser engines make it an excellent choice for boat owners seeking reliable and efficient cooling solutions.

The Sierra 18-3550 Mercruiser thermostat is a crucial component in maintaining the cooling system of your Mercruiser engine. Here are some pros and cons of purchasing this thermostat:

1. Durable: The Sierra 18-3550 Mercruiser thermostat is designed to withstand the harsh marine environment, making it a reliable and long-lasting choice.

2. Easy Installation: This thermostat is easy to install, and most users report that they were able to complete the installation process in less than an hour.

3. High Performance: The thermostat is designed to provide efficient cooling, which can help improve the overall performance of your engine.

4. OEM Quality: This thermostat is an original equipment manufacturer (OEM) replacement, which means it is made to the same specifications as the original part, ensuring a perfect fit and function.

1. Price: The Sierra 18-3550 Mercruiser thermostat can be more expensive than some aftermarket options, which may be a consideration for budget-conscious consumers.

2. Availability: This thermostat may not be readily available at all local marine parts stores, so you may need to order it online or from a specialty dealer.

3. Potential for Leaks: As with any thermostat, there is a possibility of leaks, which can lead to cooling system issues and engine damage if not addressed promptly.

The Sierra 18-3550 Mercruiser thermostat is a high-quality, durable, and reliable option for maintaining the cooling system of your Mercruiser engine. While it may be more expensive than some aftermarket alternatives, its OEM quality and efficient cooling performance make it a worthwhile investment. However, potential buyers should be aware of the possibility of leaks and the potential for availability issues.

If you are in the market for a new thermostat for your Mercruiser engine, the Sierra 18-3550 is a great choice. Its durability, easy installation, and high performance make it a worthwhile investment for boat owners who want to ensure the longevity and optimal functioning of their engine's cooling system. While it may be more expensive than some aftermarket options, the peace of mind that comes with using an OEM replacement part is priceless. Just be sure to check with your local marine parts dealer or order online to ensure availability.

Details:

Condition: New. HAZARDOUS PRODUCTS HAZMAT: 1 Carriers charge extra to ship packages with products they consider hazardous, such as oils, paints, and primers. Sierra 18-3550 Mercruiser Thermostat I/O 140D 59078 MD: Thumbnails to: PRODUCT SPECIFICATIONS: Brand. Below the price of item.

BRAND: Sierra,: Mercruiser Thermostat I/O 140D 59078, FEATURES ATRIBUTES: - 140. Unit of Measurement: EA. Manufacturer PN: 18-3550.

part #: 183550 prices

• $14.36-$35.88

specifications intengster:

• for models: Mercruiser
• brand: Sierra
• mpn: 18-3550
• part type: Thermostat
• unit of measurement: Ea

offer intengster:

• options: Ship-to-home
• started: March 5, 2025
• sold: 0
• availability: In Stock

payments intengster:

• credit card: Mastercard
• wallet: Google-pay
• other

seller intengster:

• # reviews: 70342
• city: Hollywood, Florida
• rating: 98.1%

returns intengster:

• policy: No Returns

general intengster:

• condition: New
• Boat Parts > Sterndrive Motors Components > Internal Engine Parts

shipping intengster:

• cost: $4.84
• carrier: USPS, UPS
• transit: 5-10 Days
• class: Standard, Expedited
• service: USPS First Class, USPS Priority Mail, UPS Ground, USPS Priority Mail Express
• type: Calculated

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