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Sierra 18-3651 Marine Thermostat Kit for MerCruiser GM V-8 Stern Drive 142°F

Part of: Sierra Thermostat Kit for Volvo Penta Marine Engines

Other options in this family: Sierra 18-3674 Sierra 18-3677 Sierra 18-3671 Sierra 18-3618 Sierra 18-3621

Manufacturer

Picture for manufacturer Sierra

Part Number

18-3651
12 reviews
Sale Price

$22.72

4 left at this price

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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 International 18-3651 is a complete marine thermostat kit designed for MerCruiser stern drive engines equipped with GM V-8 powerplants. Rated at 142°F (61°C), this kit provides reliable engine temperature regulation to protect your marine engine from overheating and premature wear.

Key Features:

  • Temperature rating: 142°F — optimized for MerCruiser GM V-8 applications
  • Meets or exceeds original equipment (OEM) specifications
  • Engineered to withstand the harsh marine environment
  • Complete kit includes thermostat and all necessary cover gaskets for a full service replacement

Kit Contents:

  • (1) 18-3551 Thermostat — replaces OE# 59137
  • (1) 18-2554 Thermostat Cover Gasket — replaces OE# 27-90556
  • (1) 18-2553 Thermostat Cover Gasket — replaces OE# 27-47510
  • (1) 18-2834 Thermostat Cover Gasket — replaces OE# 27-60208
  • (1) 18-2844 Thermostat Cover Gasket — replaces OE# 27-48818-1

Sierra International is the market leader in aftermarket marine engine parts, supplying many OEM engine manufacturers and boat builders. All Sierra parts meet or exceed the original equipment they replace, making the 18-3651 a trusted choice for MerCruiser thermostat replacement.

fast and easy

Simple. Great service!

My order was processed and shipped the same day, the pricing was great and loved the overall experience.

thanks!

Easy ordering and good prices

Great

Order was correct and came quicker than I expected, I will definitely use Autoplicity again.

live inventory is great... if it's true

Great customer service, received tracking number quickly.

Super fast shipping, easy to use site, would buy again from site

Too soon to tell. Took three days to ship. Best price on the web.

Very easy order to place, can't wait to get my part in!!thanks

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