HOLIDAY ALERT

We will be closing at 12 PM EST on Friday, April 18th, in observance of Good Friday and Easter.
Any orders placed after this time will be processed on Monday, April 21st.
Have a happy Easter weekend!

Weather Closure Alert

Due to severe weather, our White House, Tennesee location will be closed Wednesday the 19th.

All shipments from this location will resume on Thursday the 20th. Thank you for your patience!

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Inboard & I/O Engine Parts

Inboard Marine Engine Parts and Accessories

As the largest online dealer of inboard boat parts, Marine Parts Source will help you find the right engine parts you need for any project. We’re here to assist with seasonal maintenance, major repairs and more so you can get back on the water. Use our convenient categories to browse our collection — or if you know the part number you need, enter it into the search bar. From oil and fuel filters to spark plugs, exhaust manifolds, bell housings, starters and alternator belts, we supply boat owners from coast to coast.

You can always count on quality and knowledge when you shop with us. We’re an authorized dealer of the leading OEM and aftermarket performance inboard marine brands, including J&N Electric, Sierra, Arco Marine, Volvo Penta and Crusader. If you have a question, our sales associates have the technical expertise to answer it. Enjoy free ground shipping on qualifying orders so your vessel is ready for adventure.

Inboard & I/O Engine Parts

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  1. Sierra 18-9554-2 1 Quart 15W-40 Multi Vehicle Oil
    1 Quart 15W-40 Multi Vehicle Oil | Sierra 18-9554-2
    SIERRA-18-9554-2
    Qty In Stock: 19
    Oil 15W-40 Multi Vehicle Learn More
    MSRP: $10.59 $8.77
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  2. Small
    1 quart 25W40 4-Stroke Synthetic Blend Marine Oil | Quicksilver 92-8M0078622
    QS-92-8M0078622
    Qty In Stock: 148
    Brand: Quicksilver

    1 quart 25W40 4-Stroke Synthetic Blend Marine Oil

    Learn More
    MSRP: $14.29 $12.99
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  3. Small Image
    25W-40 Premium Blend Inboard Engine Oil, 55 gallon | Sierra 18-9400-7
    SIERRA-18-9400-7
    Qty In Stock: 0
    Brand: Sierra
    25W-40 Premium Blend Inboard Engine Oil, 55 gallon Learn More
    MSRP: $2,564.19 $1,731.72
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  4. Small Image
    25W-40 Catalyst Marine Engine Oil, 5 quart | Sierra 18-9400CAT-4
    SIERRA-18-9400CAT-4
    Qty In Stock: 165
    Brand: Sierra
    Sierra's Premium Blend 25W-40 catalyst engine oil is specially formulated to meet the needs of 4-stroke marine engines with catalyst emission systems. Learn More
    MSRP: $57.69 $38.66
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  5. Sierra 18-9553-3 Premium Blend Diesel Marine Engine Oil 15W-40 - 1 Gallon
    Premium Blend Diesel Marine Engine Oil 15W-40 - 1 Gallon | Sierra 18-9553-3
    SIERRA-18-9553-3
    Qty In Stock: 62
    Brand: Sierra

    Premium blend 15W-40 oil is specially formulated to meet the highest standards of diesel marine engine oil.

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    MSRP: $38.39 $28.43
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  6. sierra-25W-40-4-stroke-engine-oil-5QT-18-9400-4
    4-Stroke Premium Blend Marine Engine Oil 25W-40 - 5 Quart | Sierra 18-9400-4
    SIERRA-18-9400-4
    Qty In Stock: 310
    Brand: Sierra
    Sierra's Premium Blend 25W-40 engine oil is specially formulated to meet the needs of inboard & stern drive marine engines. Learn More
    MSRP: $67.29 $46.90
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  7. Small Image
    10W-30 Catalyst Marine Engine Oil, 1 gallon | Sierra 18-9420CAT-3P
    SIERRA-18-9420CAT-3
    Qty In Stock: 67
    Brand: Sierra
    Sierra's Premium Blend 10W-30 catalyst engine oil is specially formulated to meet the needs of 4-stroke outboards with catalyst emission systems. Learn More
    MSRP: $39.99 $34.06
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  8. Small Image
    25W-40 Synthetic Blend Oil, 5 quart | Sierra 18-9440-4
    SIERRA-18-9440-4
    Qty In Stock: 113
    Brand: Sierra

    Synthetic blend 25W-40 engine oil formulated for stern drive & inboard marine engines

    Learn More
    MSRP: $83.69 $53.54
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