Sierra O-Ring 18-7143-9 for OMC Sterndrive/Cobra I/O Transom Mount, 2.3-7.5 HP (1986-90), Pack of 5

The Sierra 18-7143-9 is a transom mount O-ring built for OMC Sterndrive/Cobra I/O units rated 2.3 to 7.5 HP, covering the 1986-90 model years. It is sold priced per package, with 5 O-rings included in each package, so you have enough on hand to reseal the transom mount area during service or a rebuild without having to reorder for a second job. Sierra also offers this O-ring under part number 18-7143 when purchased priced per piece; the -9 suffix designates the package-of-5 pricing and packaging. As a transom mount seal, this O-ring plays a role in maintaining a watertight barrier at the sterndrive-to-transom interface, an area that is routinely disturbed during outdrive removal, gimbal ring service, or bellows replacement. Keeping this seal in good condition and replacing it whenever the transom assembly is opened up helps prevent water intrusion into the boat.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-7143-9
• Position: Transom Mount
• Engine Type: OMC Sterndrive/Cobra I/O
• Horsepower Range: 2.3 - 7.5 HP
• Model Years: 1986-90
• Packaging: Pack of 5
• Weight: 0.02 pounds
• UPC: 808282165222

Fitment

• OMC Sterndrive/Cobra I/O, 2.3 - 7.5 HP, 1986-90, Transom Mount

Frequently Asked Questions

What does the Sierra 18-7143-9 O-ring fit? It fits OMC Sterndrive/Cobra I/O engines rated 2.3 to 7.5 HP, model years 1986-90, at the transom mount position.

How many O-rings are included in one package of the 18-7143-9? The Sierra 18-7143-9 is priced per package and includes 5 O-rings.

Is there a single-piece version of this O-ring? Yes, Sierra part number 18-7143 is the same O-ring priced per piece; the 18-7143-9 designates the package of 5.

How much does the 18-7143-9 O-ring package weigh? The package weighs 0.02 pounds.

Where on the sterndrive does this O-ring install? This O-ring installs at the transom mount on OMC Sterndrive/Cobra I/O units.

What horsepower range is this O-ring designed for? It is designed for OMC Sterndrive/Cobra I/O units in the 2.3 to 7.5 HP range.

What model years does the Sierra 18-7143-9 cover? The listed fitment for the 18-7143-9 is the 1986-90 model years.

Is the 18-7143-9 sold as a single O-ring or a set? It is sold as a set, priced per package of 5 O-rings, not as a single piece.

What is the UPC for the Sierra 18-7143-9? The UPC is 808282165222.

Is the Sierra 18-7143-9 an OMC O-ring or an OMC Cobra O-ring? It is listed for OMC Sterndrive/Cobra I/O units, covering the Cobra sterndrive line at the transom mount.