-16% sale
Sierra Not Qualified for Free Shipping Sierra Exhaust Cover Gasket #18-2839
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Sierra Sierra Exhaust Cover Gasket #18-2839 $6.32 $7.44
Sierra 18-2839 Engine GasketsSierra Exhaust Cover Gasket #18-2839OEM Interchange:MERCURY MARINE: 27-854972Gaskets: Exhaust CoverSierra Exhaust Cover Gasket #18-2839Normalized SKU: 182839UPC Code: 030999313478
Sold out -15% sale
Sierra Not Qualified for Free Shipping Sierra Transfer Port Cover Gasket #18-2838
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Sierra Sierra Transfer Port Cover Gasket #18-2838 $7.74 $9.10
Sierra 18-2838 Engine GasketsSierra Transfer Port Cover Gasket #18-2838OEM Interchange:MERCURY MARINE: 27-552791Gaskets: Port CoverSierra Transfer Port Cover Gasket #18-2838Normalized SKU: 182838UPC Code: 030999313461
Sold out -16% sale
Sierra Not Qualified for Free Shipping Sierra Baffle Plate Gasket #18-2836
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Sierra Sierra Baffle Plate Gasket #18-2836 $3.84 $4.52
Sierra 18-2836 Engine GasketsSierra Baffle Plate Gasket #18-2836OEM Interchange:MERCURY MARINE: 27-78035Gaskets: BaffleSierra Baffle Plate Gasket #18-2836Normalized SKU: 182836UPC Code: 808282258177
Sold out -17% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Base Gasket #18-2835
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Sierra Sierra Powerhead Base Gasket #18-2835 $7.98 $9.53
Sierra 18-2835 Engine GasketsSierra Powerhead Base Gasket #18-2835OEM Interchange:MERCURY MARINE: 27-692381Gaskets: PowerheadSierra Powerhead Base Gasket #18-2835Normalized SKU: 182835UPC Code: 808282258160
Sold out -15% sale
Sierra Not Qualified for Free Shipping Sierra Block Cover Gasket #18-2837
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Sierra Sierra Block Cover Gasket #18-2837 $4.05 $4.76
Sierra 18-2837 Engine GasketsSierra Block Cover Gasket #18-2837OEM Interchange:MERCURY MARINE: 27-41382Gaskets: Block CoverSierra Block Cover Gasket #18-2837Normalized SKU: 182837UPC Code: 030999313454
Sold out -16% sale
Sierra Not Qualified for Free Shipping Sierra Upper Face Plate Gasket #18-2827
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Sierra Sierra Upper Face Plate Gasket #18-2827 $2.09 $2.46
Sierra 18-2827 Engine GasketsSierra Upper Face Plate Gasket #18-2827OEM Interchange:MERCURY MARINE: 27-39623Gaskets: Face PlateSierra Upper Face Plate Gasket #18-2827Normalized SKU: 182827UPC Code: 030999313355
-15% sale
Sierra Not Qualified for Free Shipping Sierra Water Pump Base Gasket #18-2825
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Sierra Sierra Water Pump Base Gasket #18-2825 $0.82 $0.96
Sierra 18-2825 Engine GasketsSierra Water Pump Base Gasket #18-2825OEM Interchange:MERCURY MARINE: 27-32771Gaskets: Water PumpSierra Water Pump Base Gasket #18-2825Normalized SKU: 182825UPC Code: 030999313331
-15% sale
Sierra Not Qualified for Free Shipping Sierra Water Pump Base Gasket #18-2826
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Sierra Sierra Water Pump Base Gasket #18-2826 $1.89 $2.22
Sierra 18-2826 Engine GasketsSierra Water Pump Base Gasket #18-2826OEM Interchange:MERCURY MARINE: 27-85610-1MERCURY MARINE: 27-856704Gaskets: Water PumpSierra Water Pump Base Gasket #18-2826Normalized SKU: 182826UPC Code: 030999313348
Sold out -16% sale
Sierra Not Qualified for Free Shipping Sierra Lower Water Pump Gasket #18-2828
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Sierra Sierra Lower Water Pump Gasket #18-2828 $1.75 $2.06
Sierra 18-2828 Engine GasketsSierra Lower Water Pump Gasket #18-2828OEM Interchange:MERCURY MARINE: 27-39625Gaskets: Water PumpSierra Lower Water Pump Gasket #18-2828Normalized SKU: 182828UPC Code: 030999313362
-15% sale
Sierra Not Qualified for Free Shipping Sierra Upper Water Pump Gasket #18-2824
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Sierra Sierra Upper Water Pump Gasket #18-2824 $0.75 $0.88
Sierra 18-2824 Engine GasketsSierra Upper Water Pump Gasket #18-2824OEM Interchange:MERCURY MARINE: 27-19551MERCURY MARINE: 27-32770Gaskets: Water PumpSierra Upper Water Pump Gasket #18-2824Normalized SKU: 182824UPC Code: 808282258115
Sold out -15% sale
Sierra Not Qualified for Free Shipping Sierra Lower Water Pump Gasket #18-2823
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Sierra Sierra Lower Water Pump Gasket #18-2823 $2.64 $3.10
Sierra 18-2823 Engine GasketsSierra Lower Water Pump Gasket #18-2823OEM Interchange:MERCURY MARINE: 27-19553MERCURY MARINE: 27-32769Gaskets: Water PumpSierra Lower Water Pump Gasket #18-2823Normalized SKU: 182823UPC Code: 808282258108
Sold out -17% sale
Sierra Not Qualified for Free Shipping Sierra Block Cover Gasket #18-2810
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Sierra Sierra Block Cover Gasket #18-2810 $14.48 $17.28
Sierra 18-2810 Engine GasketsSierra Block Cover Gasket #18-2810OEM Interchange:MERCURY MARINE: 27-437772Gaskets: Block CoverSierra Block Cover Gasket #18-2810Normalized SKU: 182810UPC Code: 808282258078
Sold out -17% sale
Sierra Not Qualified for Free Shipping Sierra Block Cover Gasket #18-2809
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Sierra Sierra Block Cover Gasket #18-2809 $8.22 $9.81
Sierra 18-2809 Engine GasketsSierra Block Cover Gasket #18-2809OEM Interchange:MERCURY MARINE: 27-437792Gaskets: Block CoverSierra Block Cover Gasket #18-2809Normalized SKU: 182809UPC Code: 030999313201
Sold out -17% sale
Sierra Not Qualified for Free Shipping Sierra Cylinder Cover Gasket #18-2806
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Sierra Sierra Cylinder Cover Gasket #18-2806 $8.90 $10.62
Sierra 18-2806 Engine GasketsSierra Cylinder Cover Gasket #18-2806OEM Interchange:MERCURY MARINE: 27-65788Gaskets: Cylinder CoverSierra Cylinder Cover Gasket #18-2806Normalized SKU: 182806UPC Code: 030999313171
-15% sale
Sierra Not Qualified for Free Shipping Sierra Water Pump Gasket #18-2801
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Sierra Sierra Water Pump Gasket #18-2801 $1.04 $1.22
Sierra 18-2801 Engine GasketsSierra Water Pump Gasket #18-2801OEM Interchange:MERCURY MARINE: 27-32438Gaskets: Water PumpSierra Water Pump Gasket #18-2801Normalized SKU: 182801UPC Code: 030999313126
-15% sale
Sierra Not Qualified for Free Shipping Sierra Wear Plate Gasket #18-2709
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Sierra Sierra Wear Plate Gasket #18-2709 $1.77 $2.08
Sierra 18-2709 Engine GasketsSierra Wear Plate Gasket #18-2709OEM Interchange:OMC: 336530Gaskets: Wear PlateSierra Wear Plate Gasket #18-2709Normalized SKU: 182709UPC Code: 030999752918
-16% sale
Sierra Not Qualified for Free Shipping Sierra Exhaust Cover Gasket #18-2574
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Sierra Sierra Exhaust Cover Gasket #18-2574 $8.14 $9.58
Sierra 18-2574 Engine GasketsSierra Exhaust Cover Gasket #18-2574OEM Interchange:MERCURY MARINE: 27-854952Gaskets: Exhaust CoverSierra Exhaust Cover Gasket #18-2574Normalized SKU: 182574UPC Code: 030999562760
-17% sale
Sierra Not Qualified for Free Shipping Sierra Water Jacket Cover Gasket #18-2573
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Sierra Sierra Water Jacket Cover Gasket #18-2573 $8.65 $10.32
Sierra 18-2573 Engine GasketsSierra Water Jacket Cover Gasket #18-2573OEM Interchange:MERCURY MARINE: 27-721421Gaskets: Water JacketSierra Water Jacket Cover Gasket #18-2573Normalized SKU: 182573UPC Code: 030999562753
Sold out -15% sale
Sierra Strainer Cover Gasket #18-2570
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Sierra Sierra Strainer Cover Gasket #18-2570 $0.77 $0.90
Sierra 18-2570 Engine GasketsSierra Strainer Cover Gasket #18-2570OEM Interchange:MERCURY MARINE: 27-25851Gaskets: Strainer CoverSierra Strainer Cover Gasket #18-2570Normalized SKU: 182570UPC Code: 030999562722
Sold out -14% sale
Sierra Not Qualified for Free Shipping Sierra Strainer Cover Screw Gasket #18-2568
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Sierra Sierra Strainer Cover Screw Gasket #18-2568 $0.19 $0.22
Sierra 18-2568 Engine GasketsSierra Strainer Cover Screw Gasket #18-2568OEM Interchange:MERCURY MARINE: 27-25848Gaskets: Strainer CoverSierra Strainer Cover Screw Gasket #18-2568Normalized SKU: 182568UPC Code: 030999562708

Frequently Asked Questions

First Choice Marine is an online marine retailer carrying a diverse line of marine parts and accessories and related items from industry-respected and demanded manufacturers and suppliers. Through our diverse distributor network, we are able to access over 150,000 items, including our current site inventory, new products being added, and special order items. If you need it on your boat... we are your one-stop shop!

Yes, we offer FREE Shipping on most orders over $149 to US-48*.

Each product displays a shipping status message, just above the item price. Below is the meaning for each of these codes.

  • Qualifies for Free Shipping: This item qualifies for free shipping when the order is $149+
  • Qualifies for Free Ground Shipping: This item qualifies for free ground shipping when the order is $149+.
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  • In-Store Pickup Only: This item can only be picked up in our Grain Valley, MO retail store

Below the price of the item, on the product page, there is a message indicating the availability of the product.

The quantity on hand is updated as inventory events happen and matches what we have available. If you have urgent needs and we are close to what you need, contact us, and we can confirm stock.

We offer a hassle-free return policy. If you're not completely satisfied with your purchase, you can return it within 30 days for a full refund or exchange.

If you need to return an item, please follow the guidelines here so we can process a prompt refund and assist you in finding the correct item.

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