4-Position Ignition Switch Conventional, Accessory-Off-Run-Start
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SIERRA4-Position Ignition Switch Conventional, Accessory-Off-Run-Start


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Add extra coverage from the date of purchase beyond the manufacturer’s warranty.  View Details

Model # 4511978 | Mfg # MP41040UPC # 808282367732


4-Position Ignition Switch Conventional, Accessory-Off-Run-Start

Name Value
Type Switches

Product Overview

Exact OEM replacement ignition switch for Seadog part number 420375-1.

Sierra's Polyester Ignition Switch fits a standard 7/8"dia. hole and features a four-position conventional switch that provides Accessory-Off-Run-Start. Includes two keys and different key codes for added security.

Key Features

  • Maximum corrosion protection eliminates oxidation
  • Inner seal between cylinder lock and contact plate
  • Non-conductive housing eliminates potential shorts
  • Four-position conventional switch
  • Exact OEM replacement for Seadog 420375-1


  • Material: Marine-grade glass-filled polyester
  • Length: Long, 1 1/8" maximum panel thickness
  • Hole Size: 7/8"
  • Terminal Type: 4 screw tab
  • Back Up Nut: Brass
  • Face Nut: Knurled black plastic with snap-on rubber cap
  • Positions: Accessory-Off-Run-Start


  • Ignition: 15A @ 12V DC
  • Solenoid: 30A @ 12V DC
  • Accessory: 15A @ 12V DC

The Sierra Engine Parts Selector

In addition to ignition switches, 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.


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