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Sierra 18-4008 Marine Manifold Block Off Plate for Mercruiser Stern Drives

Manufacturer

Picture for manufacturer Sierra

Part Number

18-4008
11 reviews
Sale Price

$16.94

1 left at this price

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Usually delivered within 2 days

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Fitment guaranteed

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Product Details

The Sierra 18-4008 is a stainless steel block off plate (also known as a restrictor plate) designed for use on Mercruiser stern drive exhaust systems. This precision-made marine replacement part seals the riser mounting flange when a riser or elbow is not being used, making it an essential component in raw water cooling configurations.

Key Features:

  • Stainless steel construction for corrosion resistance in harsh marine environments
  • Includes bleeder hole for use with raw water cooling systems
  • Designed for riser mounting flanges with a square bolt pattern (2-13/16" x 3-1/16" bolt centers)
  • Compatible with Sierra risers 18-1971 and 18-1978
  • Manufactured to meet or exceed OEM specifications

Cross-Reference Part Numbers:

  • Barr: MC-20-60207
  • GLM: 50006
  • Mallory: 9-40540
  • Mercury Marine / Mercruiser Stern Drive: 60207
  • Osco: 60207

Sierra marine engine parts are built to deliver reliable, OEM-quality performance, making the 18-4008 a trusted aftermarket replacement for keeping your stern drive exhaust system properly sealed and functioning.

Great price & really FAST shipping

Products looks great at a price better then I found on the web.

excellent

great

The website is easy to follow and payment was a snap!

Easy shopping thank you

Good products, hope it ship's fast

Thanks

After weeks of shopping around, I was able to find the best price from Autoplicity. The ordering process was very simple since I had the option to pay through my Amazon account. Great experience.

easy website to use

Very easy to order.

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