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$21.49
In Stock (10+)
Usually delivered within 2 days
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The Sierra 18-4457 is a 4-inch external exhaust flapper valve designed to protect marine engine exhaust systems from water intrusion. This essential component prevents water from flowing back into the exhaust system when the engine is not running, which could cause serious engine damage.
Key Features:
This exhaust protector valve is a direct replacement part that helps extend engine life by keeping water out of the exhaust manifold and engine block. The EPDM material resists deterioration from saltwater, heat, and UV exposure, making it ideal for demanding marine environments.
Merc 12644A
4"
quick easy cheap
Donald L. Skiver
Thanks!
Jack
The site showed items in stock, I hope that was accurate
Ken Toporowski
I am not sure yet, I have not installed the product.
stacey Williamson
Very quick response and would do business with them anytime I could again
edemoss
Great
Jose pina
Good
Antonio flowers
This place is excellent. Very easy to use. My parts were shipped on time, and they kept me updated with multiple emails throughout the process. Would definitely buy from these guys again. A++
AClem08
The process seemed pretty simple to me. Will definitely use again.
Leonard Davis
Very convenient!
Donna Frazier
I have had a very good experience with Autoplicity and will look for more parts here. I called Customer Service and they were very good and accurate with me. It was easy, they were very nice, immediate response, and great price.
demetry
It was easy to find everything and quick
Robert Forshey
Great product and speedy service!
mattcallis
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