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Sierra 18-5603-1 Inboard Marine Starter for GM & Ford Engines

Manufacturer

Picture for manufacturer Sierra

Part Number

18-5603-1
9 reviews
Sale Price

$226.51

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-5603-1 is a noseless, counter-clockwise (CCW) top mount, rear entry gear reduction starter engineered for standard rotation GM and Ford inboard marine engines. Built to meet or exceed OEM specifications, this 12V permanent magnet gear reduction starter delivers reliable cranking power with a 1.6 kW output and a 9-tooth pinion drive.

Key Features:

  • Noseless CCW Top Mount Design – Rear entry configuration for easy installation in tight engine compartments
  • Gear Reduction Technology – Provides increased torque for dependable starts
  • Improved Marine Housing – Sealed to protect internal components from water intrusion, corrosion, and the harsh marine environment
  • 12V / 1.6 kW – Permanent magnet design with 9-tooth pinion (25.5mm OD)
  • Dual 12.3mm Unthreaded Mounting Ears – Direct bolt-on replacement
  • Direct Replacement – Can be substituted for Sierra 18-5902 and 18-5908 starters

Replaces OEM Part Numbers:

  • MerCruiser: 50-808011A05, 50-808011A1, 50-808011A3, 50-808011A4, 50-76965A1, 50-76965A3, 50-76965A4, 50-65784A1, 50-47455, 50-17251A3, 50-1725A2, 50-99419A3
  • Indmar: 573001
  • Marine Power / Pleasurecraft: 0170-000, RA122009
  • Arco: 30459

The Sierra 18-5603-1 is a trusted aftermarket solution for inboard engines used in MerCruiser, Indmar, Marine Power, and Pleasurecraft applications, offering a direct-fit replacement that installs with confidence.

Fast and easy

good descriptsion of part and pictures

Very good experience! Only wished they would have listed inside diameter of shaft..

Fast and easy

Price was better than some other places, but shipping was a bit more. Ended up being about the same price to my door. Ordered from autoplicity because they had my item in stock where my normal sourcing was out & on backorder for what I needed

tHANKS

easy to buy

good sale price and quick checkout

3 easy steps

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