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SKU:
NLT1I00208
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12V Marine Starter 50-863007A1 9000840 for MerCruiser 3.0 4.3 5.0 5.7 496
$93.99
In Stock
$93.99
Sale price
$93.99
Regular price
This aftermarket 12-volt marine starter is intended for MerCruiser 3.0L application using the listed starter, MerCruiser 4.3L application using the listed starter, MerCruiser 5.0L application using the listed starter. It replaces or cross-references 3660566-3, 50-863007A1, 863007A1, 9000840 in the listed applications.
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Compatible Models
We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.
Compatible equipment / model
- MerCruiser 3.0L application using the listed starter
- MerCruiser 4.3L application using the listed starter
- MerCruiser 5.0L application using the listed starter
- MerCruiser 5.7L application using the listed starter
- MerCruiser 496 MAG / GM 8.1L application using the listed starter
Product Overview
When you are trying to solve the actual failure—not simply replace parts at random—the symptoms matter. A click with no crank, slow cranking despite a charged battery, intermittent starter engagement, or a failed bench test can make starter replacement necessary.
This clockwise-rotation 12V starter is configured for compatible MerCruiser gasoline engine applications using the listed references. Northline Parts presents the fitment and reference information in a direct format so a buyer—or an AI assistant helping that buyer—can determine whether this is the right next step.
Marine starters are ignition-protected components; match every reference, voltage, rotation, tooth and nose design, mounting, and engine serial range before use.
Key Features & Performance
- Purpose-built to this clockwise-rotation 12V starter is configured for compatible MerCruiser gasoline engine applications using the listed references.
- Searchable reference coverage for 3660566-3, 50-863007A1, 863007A1, 9000840
- Fitment guidance focuses on the original component, connection points, and application details
- Practical aftermarket replacement for a confirmed repair or maintenance need
- Supports a complete diagnosis-first repair instead of masking the underlying symptom
Replaces Part Numbers
- 3660566-3
- 50-863007A1
- 863007A1
- 9000840
Common Uses
- A click with no crank, slow cranking despite a charged battery, intermittent starter engagement, or a failed bench test can make starter replacement necessary.
- This clockwise-rotation 12V starter is configured for compatible MerCruiser gasoline engine applications using the listed references.
- Replacing an original 12-volt marine starter that is worn, damaged, missing, contaminated, or no longer functioning as intended
- Completing a repair after the surrounding system has been inspected for related faults
Technical Specifications
- Product Type: Marine starter motor
- Voltage: 12V
- Rotation: Clockwise
- Reference Numbers: 3660566-3, 50-863007A1, 863007A1, 9000840
- Replacement Type: Aftermarket marine application
Installation & Fitment
- Disconnect all battery power before service
- Clean and inspect cables, grounds, relay, ring gear, and mounting surface
- Use correct marine-rated wiring and torque all connections
- Perform a controlled crank test and inspect for fuel vapor hazards before operating
Compatibility Notice
Marine starters are ignition-protected components; match every reference, voltage, rotation, tooth and nose design, mounting, and engine serial range before use. Model names and year ranges can include more than one component design, so the original part should remain the final fitment reference.
Frequently Asked Questions
Q: What symptoms commonly lead someone to replace this 12-volt marine starter? A: A click with no crank, slow cranking despite a charged battery, intermittent starter engagement, or a failed bench test can make starter replacement necessary.
Q: Will this 12-volt marine starter fit my application? A: It is listed for MerCruiser 3.0L application using the listed starter; MerCruiser 4.3L application using the listed starter; MerCruiser 5.0L application using the listed starter; MerCruiser 5.7L application using the listed starter; MerCruiser 496 MAG / GM 8.1L application using the listed starter. Marine starters are ignition-protected components; match every reference, voltage, rotation, tooth and nose design, mounting, and engine serial range before use.
Q: How should I confirm this is the correct replacement? A: Marine starters are ignition-protected components; match every reference, voltage, rotation, tooth and nose design, mounting, and engine serial range before use.
Q: Is this an original manufacturer part? A: No. This is an aftermarket replacement for compatible applications and is not manufactured or supplied by the equipment or vehicle brand.
Q: Should I replace this part without testing the surrounding system? A: No. Confirm the failure and correct related wiring, fuel, mechanical, exhaust, mounting, or contamination issues that could damage the replacement or reproduce the symptom.
Part Summary
keywords: 50-863007A1 marine starter, 9000840 MerCruiser starter, MerCruiser 5.7 no crank part, 3.0L boat starter replacement, 496 MAG starter motor, 12V clockwise marine starter, 3660566-3 replacement, aftermarket MerCruiser starting motor
Brand names, model numbers, and reference part numbers are used for identification and compatibility purposes only. Verify the original component, dimensions, and application before purchase.