Sierra 18-5636 Outboard Starter, Replaces 50-72467/50-64975/50-57465A1, Fits Mercury/Mariner 140 HP 6-Cyl Inline

The Sierra 18-5636 is a marine outboard starter built for Mercury and Mariner outboard motors equipped with a 140 HP 6-cylinder inline engine, covering units from serial number 4865678 and up. It is the primary electrical component responsible for cranking the outboard's powerhead to initiate combustion, and it is engineered to serve as a direct cross-reference replacement for the corresponding Mercury/Mariner OEM starter numbers. The housing is constructed of metal for durability in a marine engine compartment environment, where exposure to vibration, heat, and moisture demands a robust build.

This starter is designed as a universal fit unit within its stated engine and serial number range, meaning it is intended to bolt in without modification to qualifying 140 HP 6-cylinder inline Mercury/Mariner outboards. It measures 11 1/2 inches in length, with overall dimensions of 12 x 4.5 x 4 inches, and weighs 9 pounds. Buyers replacing a worn, weak, or failed outboard starter on a compatible Mercury/Mariner 140 HP 6-cylinder inline engine can use the 18-5636 as a like-for-like replacement using the OEM cross-reference numbers below to confirm fit before ordering.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-5636
• Material: Metal
• Weight: 9 pounds
• Length: 11 1/2 inches
• Item Dimensions (L x W x H): 12 x 4.5 x 4 inches
• Fit Type: Universal Fit
• Engine Type: 6 Cylinder Inline
• Horsepower: 140 HP
• UPC: 747730047942

Fitment

• Mercury/Mariner outboard motors, 140 HP, 6 cylinder inline engine, serial number 4865678 and up

Replaces (OEM)

• 50-72467
• 50-64975
• 50-57465A1

Frequently Asked Questions

What outboard motors does the Sierra 18-5636 starter fit? The Sierra 18-5636 is built for Mercury/Mariner outboard motors with a 140 HP 6-cylinder inline engine, covering units from serial number 4865678 and up.

Does the 18-5636 replace OEM starter numbers 50-72467, 50-64975, and 50-57465A1? Yes, the Sierra 18-5636 cross-references directly to Mercury/Mariner OEM starter numbers 50-72467, 50-64975, and 50-57465A1.

How long is the Sierra 18-5636 outboard starter? It measures 11 1/2 inches in length, with overall boxed dimensions of 12 x 4.5 x 4 inches.

What is the 18-5636 starter made of? The Sierra 18-5636 outboard starter has a metal housing for durability in a marine engine environment.

How much does the Sierra 18-5636 starter weigh? The 18-5636 weighs 9 pounds.

Is the Sierra 18-5636 a universal fit part? Yes, it is listed as a universal fit starter for the specified 140 HP 6-cylinder inline Mercury/Mariner engines with serial number 4865678 and up.

Will the 18-5636 fit a Mercury 140 Jet model outboard? No. The 140 Jet Mercury/Mariner outboards with serial number G960499 and below use a different Sierra part number, not the 18-5636.

What is the UPC for the Sierra 18-5636 starter? The UPC for the Sierra 18-5636 outboard starter is 747730047942.

Is the Sierra 18-5636 a genuine Sierra part? Yes, the 18-5636 is manufactured and sold under the Sierra brand as a replacement outboard starter.

Does the serial number of my Mercury/Mariner outboard matter for fitment? Yes. The Sierra 18-5636 is designated for 140 HP 6-cylinder inline Mercury/Mariner engines with serial number 4865678 and up, so confirming your engine's serial number against that range is important before ordering.

What does the OEM cross-reference number tell me about compatibility? Because the Sierra 18-5636 replaces Mercury/Mariner OEM numbers 50-72467, 50-64975, and 50-57465A1, you can match any of those numbers from your old starter to confirm the 18-5636 is the correct replacement.