Mercury – Starter Motor Assembly | Engine Electrical System | Marine-Grade Construction | 863007A1

Overview
A good starter motor is one of those parts you rarely think about—until the morning it fails. Anyone who’s spent time on the water knows that quiet moment right before you turn the key, when you expect the engine to come alive without hesitation. That feeling of trust matters. With this Mercury Marine part, that confidence returns. The crank sounds strong, the engagement is clean, and you know you’ll be leaving the dock instead of drifting back to the trailer in frustration. A dependable start sets the tone for the whole day, and this assembly is built to make sure that moment is always a steady one.

Key Features

• Complete starter motor assembly designed for marine V6 and V8 engines

• Features an 11-tooth pinion for proper gear engagement

• Built for bottom-mount installations with an offset bolt pattern

• Marine-grade housing and internal components designed for heat and moisture

• Direct replacement for the original starter installed by Mercury

• Meets all Mercury Marine OEM durability and performance specifications

Engine & Boat Compatibility

• Fits V6 MerCruiser sterndrive and inboard engines made by General Motors (1983–2016)

• Fits V8 MerCruiser sterndrive and inboard engines made by General Motors (1983–2016)

• Also fits MerCruiser 3.0L sterndrive engines (1999–2015)

• Common on bowriders, offshore sport boats, cabin cruisers, fishing boats, and runabouts

• Designed for engines with bottom-mount starter setups

Performance & Practical Benefits
A starter motor may seem simple, but on a marine engine it’s doing hard work—far harder than its automotive cousins. Salt air, humidity, constant heat cycles, and tight compartments all demand something stronger and more deliberate. With this Mercury Marine part, you’ll feel that strength the first time you crank the engine. The motor engages with a tight, confident click, spins smoothly, and turns the engine over with a steady surge instead of a sluggish groan.

Its marine-built construction resists the corrosion and moisture that slowly chew away at lesser hardware. The fitment is exact, so installation feels natural and secure rather than awkward or forced. Once installed, it delivers a sense of predictability you can rely on whether you’re starting up after a long winter or just refiring after a swim stop. It’s one of those upgrades that quietly improves the entire ownership experience.

Why Buy OEM
Every seasoned boater eventually learns the value of using genuine Mercury Marine parts. A starter might look like just another plug-and-play component, but the wrong tolerances or cheap internals can leave you stranded. With this OEM assembly, you’re getting engine-matched gearing, proper marine windings, and corrosion-resistant materials tested to survive real boating environments.

Choosing OEM means:

• Built to handle the heat, moisture, and vibration of marine operation

• Guaranteed alignment with Mercury engine mounting points

• Long-term reliability and fewer unexpected failures

• Better cranking performance than many aftermarket alternatives

• Confidence that the part fits and works exactly as intended

When you’re miles from the dock, that’s not just convenience—that’s peace of mind.

FAQ

Q1: Which engines does the Starter Motor Assembly 863007A1 fit?
It fits V6 and V8 MerCruiser engines made by General Motors from 1983–2016, plus MerCruiser 3.0L engines from 1999–2015.

Q2: What makes this starter different from aftermarket versions?
The marine-grade build, factory-matched gearing, and corrosion-resistant internals give it a longer, more reliable service life.

Q3: How do I confirm this is the right replacement?
Match your engine model, mounting style (bottom mount), and part number with your owner’s manual or service guide.

Q4: Is it suitable for both saltwater and freshwater use?
Yes—the housing and internal components are built specifically for marine environments.

Q5: Is installation straightforward?
Most boat owners familiar with basic engine maintenance will find it easy with common tools and clear access.