Sierra 18-3625 Thermostat
Your Price: $24.51
Save: $18.25
(42% Off $42.76)
Part # 18-3625 2nd Day Air for $2 More Eligible
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This item is found in the following Product Families
Yamaha Outboard Thermostats
Yamaha Outboard Thermostats
Mallory and Sierra Thermostats for Yamaha outboard engines.

Replaces OEM part #
  • YAMAHA 6F5-12411-03-00
  • YAMAHA 6F5-12411-01-00
  • YAMAHA 6F5-12411-02-00


  • Temperature Rating: 60 Degrees Celsius
  • Includes Seal
  • 9.9EL
  • 9.9ES
  • 15EL
  • 15ES (1986-1995)
  • 9.9L
  • 9.9S
  • 15L
  • 15S (1986-1990)
  • 9.9M
  • 15ML
  • 15MS
  • C55EL (1991-1995)
  • C25EL
  • C40EL (1991-1997)
  • C25ML (1993-1997)
  • C25MS
  • C40MS
  • C40PS (1992-1997)
  • C30EL (1991-1992)
  • CV30EL (1989-1990)
  • C40ML (1994-1995)
  • C55TL (1993-1995)
  • CV25EL
  • CV25EM
  • CV40EL(1990)
  • CV55EL (1989)
Will this fit a 90hp outboard?
This is a aftermarket part. We need your engine model number to look up a diagram of your engine to see if this part matches up to the OEM part number for your engine. Please email, chat or call in with your FULL engine information including engine manufacturer, horse power, year and model number.

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