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Sierra 18-18100 Serpentine Belt for Mercury Marine Outboard DFI Engines

Manufacturer

Picture for manufacturer Sierra

Part Number

18-18100
11 reviews
Sale Price

$79.07

In Stock (10+)

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Usually delivered within 2 days

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Product Details

The Sierra 18-18100 is a direct-replacement serpentine belt engineered for Mercury Marine outboard DFI engines. Manufactured by Sierra International — a leading supplier of marine engine parts — this belt is built to OEM specifications to ensure reliable, long-lasting performance on the water.

The serpentine belt is a critical engine component that continuously drives accessory systems including the alternator and charging circuit while the engine is running. Replacing a worn or cracked belt at regular service intervals helps prevent unexpected on-water breakdowns.

Key Features:

  • Direct OEM replacement — drop-in fit with no modifications required
  • Manufactured to Sierra International quality standards for marine applications
  • Compatible with Mercury Marine V-135/150 DFI (1998 and newer) and V-175 DFI (2001 and newer) outboard engines
  • Replaces Mercury Marine OEM part numbers 57-8285072, 57-8285074, and 57-828507Q4
  • Also interchanges with Mallory part number 9-55021

OEM / Cross-Reference Part Numbers:

  • Mercury Marine: 57-8285072, 57-8285074, 57-828507Q4
  • Mercury Sport Jet: 57-8285074, 57-828507Q4
  • Mallory: 9-55021
  • Sierra: 18-18100

Trust Sierra International for dependable marine engine maintenance parts that meet or exceed original equipment specifications.

very please

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Price was really good Easy to use web site

Fast, Hassle free and easy

Great product, great service A++

So far so good just checked out

so far so good

good so far, just ordered a part not available anywhere but autoplicity

Shopped all around for a new battery for my wife's custom car and found Autoplicity's prices hard to beat!!!

Ordered a couple K&N oil filters for my bike and they were the cheapest by far. The order arrived quickly and exactly as promised. They kept me informed of the status all the way. i would definitely buy from them again! Ed

Great prices very fast shipping!!!

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