18-2732-9 Exhaust Connectors & Shutters for MerCruiser, 4", (Qty. 2 of 18-2732)
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SIERRA18-2732-9 Exhaust Connectors & Shutters for MerCruiser, 4", (Qty. 2 of 18-2732)


In stock online.
Model # 6936488 | Mfg # 18-2732-9UPC # 808282166823


18-2732-9 Exhaust Connectors & Shutters for MerCruiser, 4", (Qty. 2 of 18-2732)

Name Value
Compatibility Mercruiser Stern Drive
Dimensions 4"
Type Shutters

Product Overview

An added line of defense against exhaust backflow.

Many exhaust installations include shutters to prevent water from traveling back up the exhaust and into riser and manifold. These water shutters are exposed to endless heat cycling and saltwater abuse that can speed up the corrosion process and cause failure; routine inspection and replacement is advised. Sierra has engineered these water shutters to match the OEM shutters on many MerCruiser installations and protect water from traveling back into the engine from the exhaust.

Key Features

  • Engineered to meet or exceed manufacturer specifications
  • Sold in pairs (single connector and shutter p/n 18-2732)
  • Protects sensitive engine components from being damaged by water traveling back through exhaust system
  • Fits all MerCruiser #1 drives
  • Backed by SeaStar Solutions Limited Two-Year Warranty

The Sierra Engine Parts Selector

In addition to water shutters, we offer a wide variety of other engine parts manufactured by Sierra. To see if we have the part you need, see our Engine Parts Selector, where you can search by engine make, serial number and model or year of manufacture.

ApplicationOEM Part Number
MerCruiser Sterndrive807166A3, 14348A1, 14348, 14348A2


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