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Sierra 18-3425 Yamaha Outboard Water Pump Impeller Repair Kit 663-W0078-00-00

Manufacturer

Picture for manufacturer Sierra

Part Number

18-3425
12 reviews
Sale Price

$93.90

In Stock (6)

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Usually delivered within 2 days

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Product Details

The Sierra 18-3425 is a complete water pump impeller repair kit designed as a direct replacement for Yamaha outboard engines. This kit replaces Yamaha OEM part numbers 663-W0078-00-00 and 663-W0078-A0-00, as well as Mercury Marine part numbers 84188M and 84188T, making it a versatile solution for cooling system maintenance on compatible 2-stroke outboard motors.

Sierra's water pump kits are engineered to meet or exceed OEM specifications, ensuring reliable cooling system performance and protecting your outboard engine from overheating. This kit does not include the pump housing.

Kit Contents:

  • 18-3069 Impeller — replaces OEM# 47-81423M, 47-97108M, 6H3-44352-00-00
  • 18-3435 Insert Cup — replaces OEM# 663-44322-00-00
  • 18-0292 Wear Plate to Pump Housing Gasket — replaces OEM# 27-81417M, 663-44315-A0-00
  • 18-0294 Wear Plate to Pump Base Gasket — replaces OEM# 663-44324-A0-00
  • Impeller Plate — replaces OEM# 663-44323-00-00
  • (2) 18-0256 Bolts — replaces OEM# 97395-08045-00

OEM Cross-Reference Part Numbers:

  • Yamaha: 663-W0078-00-00
  • Yamaha: 663-W0078-A0-00
  • Mercury Marine: 84188M
  • Mercury Marine: 84188T

Regular water pump maintenance is essential for preventing engine overheating. Sierra's 18-3425 kit provides all the necessary components for a thorough impeller service on compatible Yamaha 55 HP 2-stroke outboard motors.

great prices great service will make a purchase again

shopping was easy

Easy to find part and verify fit, price is low shipping not outrageous.

Bought a new air intake for my Ford Raptor... Got it in the time they said id get it and for a great price too ...had to call a few times to see the status because it came from the manufacturer wasn't really a big issue customer service was very helpful all the times I talked to them very very happy with my new intake and will be glad to reccommend or use autoplicity again

Least expensive around and previous experiences make me not shy to buy from again.

Quick and easy...

Great prices... Easy transaction

I ordered CV axles from Autoplicity and had them in less than a week! Definitely the best prices for quality product on this item. Will be a return customer for sure!

Easy to find the part I was looking for. Looks like the shipping will be quick. Thanks!

Great experience

first order from this website-great pricing and shipping costs

Easy to use website, would use again. Had the hard to find part I needed.

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