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Sierra 18-3408 Yamaha Outboard Water Pump Kit with Housing 2-Stroke

Manufacturer

Picture for manufacturer Sierra

Part Number

18-3408
13 reviews
Sale Price

$69.37

In Stock (5)

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Usually delivered within 2 days

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Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-3408 is a complete water pump replacement kit with housing designed for Yamaha 2-stroke outboard motors. Built to meet OEM specifications, this kit delivers everything needed to fully rebuild the cooling system water pump, helping prevent engine overheating and extending outboard life.

OEM Cross-Reference Numbers:

  • Yamaha 6H4-W0078-A00-00
  • Yamaha 6H4-W0078-00-00
  • Yamaha 6H4-W0078-01-00
  • Yamaha 6H4-W0078-A0-00
  • Yamaha 663-44311-02-00

Kit Includes:

  • Water Pump Housing
  • Impeller (18-3435)
  • Insert Cup (18-3297)
  • Impeller Key (18-0297)
  • Wear Plate (18-3436)
  • Water Pump Gasket (18-0294)
  • Water Pump Gasket (18-0256)
  • Water Pump Bolt (18-0292)
  • Oil Seal (18-99149)
  • Water Pump Bolt (18-3068)

Key Features:

  • Meets or exceeds OEM specifications for reliable fit and performance
  • Complete housing-included kit — no separate housing purchase required
  • Same core components as Sierra 18-3429, but includes the water pump housing
  • Designed for Yamaha 40 HP and 50 HP 2-stroke, 3-cylinder outboards (1984–1987)
  • Direct drop-in replacement — no modifications required

Regular water pump impeller replacement is essential preventive maintenance for any outboard engine. The Sierra 18-3408 kit simplifies the process by supplying all critical components in a single package, ensuring your Yamaha outboard's cooling system is fully restored to proper working order.

Products specifications

Description

Repair Kit w/ Housing

OEM Number

6H4-W0078-00, A0, 663-44311-02

So Far So good

Found exactly what I was looking for and for a good price. The checkout is nice and simple and easy to use. However, when I sent them an email before my order shipped saying that I need to have one item removed from the order, I never got an answer and my

Great service

Best product & shipping prices found! Thanks! We look forward to doing more business with Autoplicity.

Easy site to work with, good representation of products.Extremely fair prices.

Had the absolute best price for a bike carrier. Quick shipping, lots of email feedback so you know what's happening to your order. Highly recommended! AAAAA++++++++++++

Very fast shipping, always great prices.

I'm always had a great experience!

Fast and easy. Good prices

Excellent price on kirkey seats! I will be buying from them again. Thanks for the prompt service

Fast Shiping Good Services Verry Good Pricing

The lowest price on the internet for this part and they shipped it fast!!!! This was definitely a very good experience!<br>I will gladly buy parts from this company again!

Wow super fast shipping and I ordered over a holiday weekend. Will be doing business with this site again soon.

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