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Engine Coupler for MerCruiser Mercury Sierra 3.0L 4 Cyl 12632A6 18-2321
$527.99
Sale price
$527.99
Regular price
Available to Order
This Engine Coupler is a marine coupling component compatible with MerCruiser, Mercury, and Sierra 3.0L 4-cylinder engines and matches OEM Part# 12632A6, 18-2321, 9-72506.
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I needed a forklift part and wasn’t sure which one fit. They asked for the model and serial number, got back to me quickly, and made sure I ordered the right one. Really helpful.
Randy W. — Verified customer
Product Overview
This engine coupler transfers torque from the engine to the drive shaft in MerCruiser, Mercury, and Sierra 3.0L 4-cylinder marine applications. Designed for direct replacement, it ensures smooth power delivery and reliable connection between the engine and outdrive. Ideal for boat owners and marine mechanics seeking a durable OEM-spec coupler for their 3.0L 4-cylinder stern drive.
Key Features & Performance
- Precision-engineered splines for secure fitment with MerCruiser and Mercury drive shafts
- Constructed from high-strength steel to withstand marine torque loads
- Direct replacement for OEM part numbers 12632A6, 18-2321, and 9-72506
- Corrosion-resistant finish protects against saltwater and freshwater environments
- Matches factory specifications for reliable long-term operation
Fitment & Compatibility
- Compatible with MerCruiser 3.0L 4-cylinder engines (1985���2000 models)
- Compatible with Mercury Marine 3.0L 4-cylinder engines
- Compatible with Sierra aftermarket drive systems using OEM equivalent parts
- Replaces OEM part numbers: 12632A6, 18-2321, 9-72506
Common Uses
- Replacement of worn or damaged engine couplers in MerCruiser Alpha One and Alpha One Gen II drives
- Marine engine-to-outdrive torque transfer in stern drive boats
- Service and repair of 3.0L 4-cylinder gasoline marine engines
Technical Specifications
- Part Number(s): 12632A6, 18-2321, 9-72506
- Material: High-strength steel
- Application: 3.0L 4-cylinder MerCruiser / Mercury / Sierra
- Drive Type: Stern drive
Frequently Asked Questions
Q: Is this engine coupler a direct replacement for my MerCruiser 3.0L? A: Yes, it directly replaces OEM part numbers 12632A6, 18-2321, and 9-72506 for MerCruiser 3.0L 4-cylinder engines from 1985���2000.
Q: What is the spline count on this coupler? A: This coupler has the standard 17-spline configuration used on Alpha One and Alpha One Gen II drives.
Product appearance and specifications may vary slightly by batch. Compatibility may vary by serial number. Verify fitment before purchase.