Sold out -17% sale
Sierra Not Qualified for Free Shipping Sierra Exhaust Manifold Gasket Set #18-4346
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Sierra Sierra Exhaust Manifold Gasket Set #18-4346 $8.26 $9.86
Sierra 18-4346 Engine GasketsExhaust Manifold Gasket SetOEM Interchange:CHRYSLER INBOARD: 3745220Sierra Exhaust Manifold Gasket Set #18-4346Normalized SKU: 184346UPC Code: 808282237738
-17% sale
Sierra Not Qualified for Free Shipping Sierra Exhaust Manifold Gasket Set #18-4347-1
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Sierra Sierra Exhaust Manifold Gasket Set #18-4347-1 $29.76 $35.52
Sierra 18-4347-1 Engine GasketsExhaust Manifold Gasket SetSierra Exhaust Manifold Gasket Set #18-4347-1Normalized SKU: 1843471UPC Code: 808282236731
Sold out -22% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4340
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Sierra Sierra Powerhead Gasket Set #18-4340 $165.54 $210.24
Sierra 18-4340 Engine GasketsPowerhead Gasket SetOEM Interchange:MERCURY MARINE: 27-13461A99Sierra Powerhead Gasket Set #18-4340Normalized SKU: 184340UPC Code: 808282146153
Sold out -20% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4339
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Sierra Sierra Powerhead Gasket Set #18-4339 $87.91 $109.13
Sierra 18-4339 Engine GasketsPowerhead Gasket SetOEM Interchange:MERCURY MARINE: 27-14697A87Sierra Powerhead Gasket Set #18-4339Normalized SKU: 184339UPC Code: 808282146146
Sold out -20% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4336
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Sierra Sierra Powerhead Gasket Set #18-4336 $95.86 $119.00
Sierra 18-4336 Engine GasketsPowerhead Gasket SetOEM Interchange:MERCURY MARINE: 27-43004A99Sierra Powerhead Gasket Set #18-4336Normalized SKU: 184336UPC Code: 808282146115
Sold out -20% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4337
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Sierra Sierra Powerhead Gasket Set #18-4337 $78.10 $96.95
Sierra 18-4337 Engine GasketsPowerhead Gasket SetOEM Interchange:MERCURY MARINE: 27-812867A97Sierra Powerhead Gasket Set #18-4337Normalized SKU: 184337UPC Code: 808282146122
Sold out -17% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4338
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Sierra Sierra Powerhead Gasket Set #18-4338 $45.65 $54.77
Sierra 18-4338 Engine GasketsPowerhead Gasket SetOEM Interchange:MERCURY MARINE: 27-814754A00Sierra Powerhead Gasket Set #18-4338Normalized SKU: 184338UPC Code: 808282146139
Sold out -20% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4334
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Sierra Sierra Powerhead Gasket Set #18-4334 $88.80 $110.23
Sierra 18-4334 Engine GasketsPowerhead Gasket SetOEM Interchange:MERCURY MARINE: 27-41499A87Sierra Powerhead Gasket Set #18-4334Normalized SKU: 184334UPC Code: 808282146092
-17% sale
Sierra Not Qualified for Free Shipping Sierra Crankshaft Seal Kit #18-4331
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Sierra Sierra Crankshaft Seal Kit #18-4331 $23.79 $28.40
Sierra 18-4331 Engine GasketsCrankshaft Seal KitSierra Crankshaft Seal Kit #18-4331Normalized SKU: 184331UPC Code: 808282106072
Sold out -17% sale
Sierra Crankshaft Seal Kit #18-4330
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Sierra Sierra Crankshaft Seal Kit #18-4330 $38.88 $46.66
Sierra 18-4330 Engine GasketsCrankshaft Seal KitSierra Crankshaft Seal Kit #18-4330Normalized SKU: 184330UPC Code: 808282109899
-17% sale
Sierra Not Qualified for Free Shipping Sierra Crankshaft Seal Kit #18-4329
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Sierra Sierra Crankshaft Seal Kit #18-4329 $44.42 $53.30
Sierra 18-4329 Engine GasketsCrankshaft Seal KitSierra Crankshaft Seal Kit #18-4329Normalized SKU: 184329UPC Code: 808282159337
-17% sale
Sierra Crankshaft Seal Kit #18-4332
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Sierra Sierra Crankshaft Seal Kit #18-4332 $31.48 $37.57
Sierra 18-4332 Engine GasketsCrankshaft Seal KitSierra Crankshaft Seal Kit #18-4332Normalized SKU: 184332UPC Code: 808282105839
-17% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4326
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Sierra Sierra Powerhead Gasket Set #18-4326 $63.98 $76.77
Sierra 18-4326 Engine GasketsPowerhead Gasket SetOEM Interchange:MERCURY MARINE: 27-43779A87Sierra Powerhead Gasket Set #18-4326Normalized SKU: 184326UPC Code: 808282111960
Sold out -17% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4323
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Sierra Sierra Powerhead Gasket Set #18-4323 $17.93 $21.40
Sierra 18-4323 Engine GasketsPowerhead Gasket SetOEM Interchange:OMC: 436891Sierra Powerhead Gasket Set #18-4323Normalized SKU: 184323UPC Code: 030999875785
Sold out -17% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4322
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Sierra Sierra Powerhead Gasket Set #18-4322 $72.99 $87.59
Sierra 18-4322 Engine GasketsPowerhead Gasket SetOEM Interchange:OMC: 432570Sierra Powerhead Gasket Set #18-4322Normalized SKU: 184322UPC Code: 030999753960
Sold out -20% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4325
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Sierra Sierra Powerhead Gasket Set #18-4325 $73.41 $91.13
Sierra 18-4325 Engine GasketsPowerhead Gasket SetOEM Interchange:MERCURY MARINE: 27-85491A90Sierra Powerhead Gasket Set #18-4325Normalized SKU: 184325UPC Code: 808282103378
Sold out -17% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4321
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Sierra Sierra Powerhead Gasket Set #18-4321 $52.73 $63.27
Sierra 18-4321 Engine GasketsPowerhead Gasket SetOEM Interchange:OMC: 398047Sierra Powerhead Gasket Set #18-4321Normalized SKU: 184321UPC Code: 808282259204
Sold out -17% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4318
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Sierra Sierra Powerhead Gasket Set #18-4318 $19.64 $23.44
Sierra 18-4318 Engine GasketsPowerhead Gasket SetOEM Interchange:OMC: 390076Sierra Powerhead Gasket Set #18-4318Normalized SKU: 184318UPC Code: 030999753939
-22% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4319
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Sierra Sierra Powerhead Gasket Set #18-4319 $186.29 $236.61
Sierra 18-4319 Engine GasketsPowerhead Gasket SetOEM Interchange:MERCURY MARINE: 27-11338A88MERCURY MARINE: 27-89221A88Sierra Powerhead Gasket Set #18-4319Normalized SKU: 184319UPC Code: 030999753946
Sold out -22% sale
Sierra Not Qualified for Free Shipping Sierra Powerhead Gasket Set #18-4317
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Sierra Sierra Powerhead Gasket Set #18-4317 $191.77 $243.57
Sierra 18-4317 Engine GasketsPowerhead Gasket SetOEM Interchange:MERCURY MARINE: 27-90484A88Sierra Powerhead Gasket Set #18-4317Normalized SKU: 184317UPC Code: 030999563293

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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