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Sierra 18-3647 Thermostat Kit for MerCruiser GM V6 V8 Engines 160°F

Manufacturer

Picture for manufacturer Sierra

Part Number

118-3647
6 reviews
Sale Price

$26.02

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-3647 Thermostat Kit is a complete replacement thermostat assembly designed for 1987 and newer GM-based MerCruiser engines with standard cooling systems. This premium aftermarket kit features a 160°F temperature rating and is engineered to meet or exceed OEM specifications for reliable engine temperature regulation.

Complete Kit Includes:

  • 18-3649 Thermostat (160°F)
  • 18-2844 Thermostat Cover Gasket
  • 18-2552 Thermostat Cover Gasket
  • 18-2553 Thermostat Cover Gasket
  • 18-7173 O-Ring
  • 18-2917 Thermostat Housing Gasket

This comprehensive kit eliminates the need to source individual components, providing everything required for a proper thermostat replacement in one package. A properly functioning thermostat is essential for maintaining optimal engine temperature, ensuring peak performance and fuel efficiency.

OEM Replacement Numbers: Mercury Marine 807252Q5, 807252T8, 8M0091470, 8M0109441 | Mallory 9-43157 | GLM 13101 | EMP 75-03222 | Pro Marine 64252K2

Seems to have worked so far

Great product and price. Customer service and communication above and beyond. Highly recommend.

I had a return that went very smoothly!

Great!

I had ordered some CM-19546-A2 (friction-modifier for posi-traction differentials with carbon-fiber clutches) from CJ Pony Parts, and it arrived broken and had all leaked out. I spent $25.42 for nothing, and they still have not responded to my complaint. I bought 2 bottles from THMotorsports in hopes that ONE would arrive undamaged. They arrived in a box, not a bubble mailer like CJ, and both bottles were intact and undamaged. If you're going to buy specialty automotive fluids online, THMotorsports is the better place to do so.

The tool I ordered came quickly, I've tested it out already, works great. Very pleased. Thanks!

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