Sierra 18-3704 Propeller Lock Nut
Price: $14.99
Save: $2.40
(13% Off $17.39)
Part # 18-3704
2nd Day Air for $2.99 More Eligible
SHIPS TODAY!* if ordered in 2 hrs 49 mins.
This item is found in the following Product Families
Replaces OEM part #
  • MERCURY MARINE 11-69578
  • MERCURY MARINE 11-69578Q1
  • MERCURY MARINE 11-69578A1
  • MERCURY MARINE 11-69578A2

Propeller Nut for Mercury, Mariner 11-69578A1 11-69578Q1, GLM 21240 21260

Average Customer Review for Sierra 18-3704 Propeller Lock Nut
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Good to go
by Johnson from Millbrook, Alabama on March 01, 2015
Machine work, materials and fit were top drawer.
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Great ser.
by Mike from Hopkinsville, Kentucky on August 16, 2013
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What is the thread size?
Sierra can only match it up by engine application. There are no specs on this.

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