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Sierra 18-7459 Thermostat O-Ring for MerCruiser / Mercury Marine

Manufacturer

Picture for manufacturer Sierra

Part Number

18-7459
6 reviews
Sale Price

$4.54

In Stock (6)

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Usually delivered within 2 days

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Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-7459 is a replacement thermostat O-ring engineered to OEM specifications for MerCruiser and Mercury Marine engines. Designed specifically for thermostat housings with a flat cover plate, this O-ring provides a reliable, leak-free seal in demanding marine cooling system applications.

Manufactured from durable, non-corrosive rubber materials, the 18-7459 resists the harsh effects of saltwater, freshwater, and elevated engine temperatures. Maintaining a proper seal at the thermostat housing is critical to regulating coolant flow and protecting your engine from overheating.

Specifications:

  • Inner Diameter (I.D.): 2.234"
  • Width: 0.139"
  • Material: Marine-grade rubber
  • Application: Thermostat housing with flat cover plate

OEM Cross-Reference Numbers:

  • Mercury Marine / MerCruiser: 20311, 25-20826

Sierra marine engine parts are built to meet or exceed original equipment manufacturer standards, making the 18-7459 a direct-fit, drop-in replacement. Sold individually.

No other site listed my vehicle (2004 Tacoma SR5) for the parts I needed so I was afraid of getting the wrong parts. Then I found Autoplicity and they not only had my vehicle listed but they had the parts I needed, and at a great price. Very Happy with my entire experience from start to finish. Thanks Guys!!!

Ordering was easy and fast

Best price for the item I needed. Very fast shipping and there consumer service was great on the phone.

reasonable prices and free ship

Ordering was a snap, everyone else had it on back order, please let me know if it is on back order.

Quick and easy

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