65 Amp Alternator – Fits MerCruiser 4.3L, 5.0L, 5.7L, 6.2L & 8.1L Engines (Replaces 863077T)
65 Amp Alternator – Fits MerCruiser 4.3L, 5.0L, 5.7L, 6.2L & 8.1L Engines (Replaces 863077T) is backordered and will ship as soon as it is back in stock.
Couldn't load pickup availability
Worry-free returns
Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
65 Amp Alternator – Fits MerCruiser 4.3L, 5.0L, 5.7L, 6.2L & 8....
Product Details
This is a direct-fit 65 Amp Alternator – Fits MerCruiser 4.3L, 5.0L, 5.7L, 6.2L & 8.1L Engines (Replaces 863077T), designed as a Delco-style alternator with a serpentine belt pulley. It is engineered for MerCruiser sterndrive and inboard engines from 2001 through 2016, including the 100 Vazer, V6, V8, 496 Magnum, 496 HO, and 8.1L models.
It serves as a direct replacement for Mercury part numbers 863077T, 863077-1, and 8M0095472, as well as Delco 19020611, 19020612, Arrowhead ADR0316, and Sierra 18-6298.
- Installation: Mounts as a direct replacement using the J180 hinge standard.
- Certification: SAE J1171 & ISO 8846 Marine Certified for ignition protection.
- Included: Comes as a complete alternator assembly.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 863077T |
| Mercury | 863077-1 |
| Mercury | 8M0095472 |
| Delco | 19020611 |
| Delco | 19020612 |
| Arrowhead | ADR0316 |
| Sierra | 18-6298 |
Engine & Model Compatibility
Confirm your engine model and year in the tables below to ensure proper fitment.
MerCruiser Sterndrive Engines
| Model | Rated HP | Years | OEM Part No. | Notes |
|---|---|---|---|---|
| 4.3L (Carb.) Alpha & Bravo | 262 HP | 2002–2016 | 863077T | |
| 4.3L (MFI) Alpha & Bravo | 262 HP | 2002–2016 | 863077T | |
| 4.3L MPI | 262 HP | 2001–2002 | 863077T | |
| 5.0L (2-BBL) (Gen+) | 305 HP | 1998–2002 | 863077T | Serial 0M3200025 through 2A528897 |
| 5.0L (Carb.) Alpha & Bravo | 305 HP | 2002–2016 | 863077T | |
| 5.0L MPI Alpha & Bravo | 305 HP | 2001–2016 | 863077T | |
| 5.7L (2-BBL) (Gen+) | 350 HP | 1998–2002 | 863077T | Serial 0M3200025 through 2A528897 |
| 5.7L (Carb.) Alpha & Bravo | 350 HP | 2002–2016 | 863077T | |
| 350 Mag MPI Alpha & Bravo | 350 HP | 2001–2016 | 863077T | |
| 350 Mag MPI Hor Alpha & Bravo | 350 HP | 2001–2016 | 863077T | Horizon model |
| MX 6.2L MPI | 377 HP | 2000–2016 | 863077T | |
| MX 6.2L MPI Horizon | 377 HP | 2000–2016 | 863077T | |
| 496 Mag | 496 HP | 2001–2016 | 863077T | |
| 496 Mag HO | 496 HP | 2001–2016 | 863077T | High Output model |
MerCruiser Inboard Engines
| Model | Rated HP | Years | OEM Part No. | Notes |
|---|---|---|---|---|
| 5.7L EFI (Gen+) | 350 HP | 1998–2016 | 863077T | |
| 5.7L MIE | 350 HP | 1999–2016 | 863077T | |
| 350 Mag MPI | 350 HP | 1999–2016 | 863077T | Gen+ |
| 350 Mag MPI Horizon | 350 HP | 1999–2016 | 863077T | |
| MX 6.2L MPI | 377 HP | 2001–2016 | 863077T | |
| MX 6.2L MPI Horizon | 377 HP | 2001–2016 | 863077T | |
| 8.1S Horizon | 496 HP | 2001–2016 | 863077T | |
| 8.1S HO | 496 HP | 2001–2016 | 863077T | High Output model |
MerCruiser Ski & Performance Engines
| Model | Rated HP | Years | OEM Part No. | Notes |
|---|---|---|---|---|
| Black Scorpion Ski (Gen+) | 350 HP | 1997–2016 | 863077T | |
| 5.7L Ski (CARB) | 350 HP | 1998–2016 | 863077T | |
| MX 6.2L BS MPI Ski | 377 HP | 2001–2016 | 863077T | |
| 377 Scorpion | 377 HP | 1997–2016 | 863077T | |
| 377 Scorpion HO EC | 377 HP | 2000–2016 | 863077T | High Output model |
| 500 EFI | 502 HP | 2000–2002 | 863077T | |
| 525 EFI | 502 HP | 2000–2002 | 863077T | |
| 600SCI | 2002–2016 | 863077T | ||
| 662SCI | 2002–2016 | 863077T | ||
| 700SCI | 2002–2016 | 863077T | ||
| 100 Vazer | 2001–2016 | 863077T |
Technical Specs
- Product Type
- Marine Alternator
- Output
- 65-70 Amp
- Voltage
- 12V
- Rotation
- Clockwise
- Mounting
- J180 Hinge
- Belt Type
- Serpentine
- Pulley Grooves
- 6
- Pulley Diameter
- 50mm (1.97")
- B+ Output
- M6
- Terminal Type
- Connector for I Terminal, No R Terminal
- Remote Sense
- No
- Polarity
- Negative
- Housing
- Black
- Weight
- 4.59 kg (10.11 lbs)
- Dimensions
- 22cm L x 20cm W x 20cm H
What’s in the Box
- 1 x Alternator Assembly (Replaces 863077T)
Installation Notes
- Disconnect the boat's battery terminals to prevent electrical shorts.
- Loosen the belt tensioner and remove the serpentine belt from the alternator pulley.
- Identify and carefully disconnect the electrical wiring from the back of the old alternator.
- Remove the mounting bolts securing the alternator to the engine bracket.
- Lift the old alternator out of the engine bay.
- Position the new alternator and secure it with the original mounting bolts.
- Reconnect the electrical connectors to the appropriate terminals.
- Re-install the serpentine belt and apply correct tension using the tensioner.
- Reconnect the battery terminals.
- Start the engine and use a multimeter to verify the charging system output is within specification (typically 13.5V-14.5V).
Troubleshooting & FAQ
How do I confirm this alternator fits my specific engine?
The surest way is to match the part number from your old alternator to one of the cross-references in the Part Number Matrix. If you can't find a number, use the Engine & Model Compatibility tables to find your engine model and year.
Is this a 65 Amp or 70 Amp alternator?
This unit is sold as a 65-70 amp replacement. While the original Mercury specification is 65 amps, some aftermarket suppliers rate it at 70 amps. It is a direct fit and electronically compatible replacement for the original 863077T and its equivalents, regardless of the amp rating discrepancy.
What are common signs of a failing alternator?
Symptoms include dimming dash lights, a battery warning light on your console, a frequently dead or weak battery, and sometimes a grinding or whining noise coming from the engine bay. You may also notice electrical components operating poorly at low RPMs.
Is this part different from the original OEM part?
This is an aftermarket part designed to meet or exceed OEM specifications for fit, form, and function. It offers comparable performance and reliability to the original Delco or Mercury alternator at a better value.
What is the difference between OEM and aftermarket parts?
This listing is for an aftermarket replacement, not an OEM part. It is built to OEM-level specifications with comparable materials in an ISO 9002 certified facility and is batch-inspected for quality and consistency.
What are the shipping speed and cost?
We ship worldwide quickly—typical transit time is 5–15 days. Standard shipping is free to most regions, with expedited options available at checkout where applicable.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal marine use. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard window for unused items in their original condition. See our full policy page or contact us for instructions.
Safety & Important Info
- Verify images and specifications against your original part before ordering. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement component, not an original equipment manufacturer (OEM) part.
- Professional installation is highly recommended for safety, performance, and to prevent damage to the electrical system.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and rigorously tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery on most orders, reaching you in 5–15 days worldwide.
- Manufacturer-Direct Value — We deliver fair pricing without compromising on materials or quality control.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
