Sierra Serpentine Belt 18-18100, White, for Mercury V-135/150 DFI (1998-up) and V-175 DFI (2001-up) Outboards

The Sierra 18-18100 is a white serpentine belt built as a direct replacement for the accessory drive belt on Mercury V-135/150 DFI (1998-up) and V-175 DFI (2001-up) outboard engines. Serpentine belts run the engine's accessory drive system, and a worn, cracked, or glazed belt can cause slipping, squealing, or a complete loss of accessory drive, so keeping this belt in good condition is important for reliable operation on the water. This Sierra-branded belt is sized to match the original equipment fitment for the V-135/150 DFI and V-175 DFI engine applications, making it a straightforward swap for a boat owner or marine technician performing routine maintenance or replacing a failed belt.

The belt measures 13 inches long by 4 inches wide and is finished in white. It is packaged as a single belt (1 count) and ships at 0.26 pounds. Because it is a direct-fit replacement for the specified Mercury DFI outboard applications, no modification is required for installation. Keep a spare on hand for offshore or extended trips, since a snapped serpentine belt can leave an outboard without accessory drive function until it is replaced.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-18100
• Product Type: Serpentine Belt
• Color: White
• Dimensions: 13 inches L x 4 inches W
• Weight: 0.26 pounds
• Unit Count: 1 belt
• UPC: 808282200091

Fitment

• Mercury V-135/150 DFI (1998-up)
• Mercury V-175 DFI (2001-up)

Replaces (OEM)

• Mallory 9-55021
• Mercury Marine 57-8285072
• Mercury Marine 57-8285074
• Mercury Marine 57-828507Q4

Frequently Asked Questions

What engines does the Sierra 18-18100 serpentine belt fit? This belt fits Mercury V-135/150 DFI outboards from 1998-up and Mercury V-175 DFI outboards from 2001-up.

Is the Sierra 18-18100 a direct OEM replacement? Yes, the 18-18100 is designed as a direct-fit replacement belt for the specified Mercury V-135/150 DFI and V-175 DFI outboard applications, requiring no modification to install.

What size is the 18-18100 serpentine belt? The belt measures 13 inches long by 4 inches wide.

What color is the Sierra 18-18100 belt? It is white.

How much does the 18-18100 serpentine belt weigh? The Sierra 18-18100 weighs 0.26 pounds.

What OEM part numbers does the 18-18100 cross-reference to? This belt interchanges with Mallory 9-55021 and Mercury Marine 57-8285072, 57-8285074, and 57-828507Q4.

How many belts come in one order of the 18-18100? One order includes a single serpentine belt, sold individually.

Will the 18-18100 belt fit a Mercury Sport Jet engine? The 18-18100 cross-references to Mercury Sport Jet belt numbers 57-8285074 and 57-828507Q4, so it is a match for those Sport Jet applications in addition to the V-135/150 DFI and V-175 DFI outboards.

What are the signs a serpentine belt like the 18-18100 needs to be replaced? Squealing, visible cracking or glazing on the belt surface, or slipping accessory drive components are common signs the belt should be replaced; the Sierra 18-18100 is sized to directly replace a worn original belt on the covered Mercury DFI engines.

Is the Sierra 18-18100 an OEM or aftermarket belt? The 18-18100 is a Sierra-branded aftermarket belt manufactured to match the fit and function of the original equipment belt on the specified Mercury DFI outboard engines.

Does the 18-18100 require any additional hardware to install? No additional hardware is included or required; the 18-18100 is a single replacement belt sized for direct installation on the covered Mercury V-135/150 DFI and V-175 DFI engines.