Arco 5415 Replacement Starter – Mercury 80–115 HP 4-Stroke & 80 HP Jet Optimax
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Arco 5415 Replacement Starter Motor
The Arco 5415 is a direct-fit replacement starter for Mercury Marine 4-stroke outboards in the 80–115 HP range, including the 2009–2010 80 HP Jet Optimax. It replaces Mercury part numbers 879345T77 and 8M0038387 with a precise OEM-spec fit — no modifications required. Whether your Mercury 4-stroke is cranking slowly or the starter has failed outright, the 5415 restores reliable starting performance and installs exactly like the original.
Compatible Applications
- Mercury Marine 80 HP 4-stroke outboard engines
- Mercury Marine 90 HP 4-stroke outboard engines
- Mercury Marine 115 HP 4-stroke outboard engines
- Mercury 80 HP Jet Optimax engines (2009–2010)
Replaces OEM Part Numbers
- Mercury: 879345T77, 8M0038387
Key Features
- Direct OEM replacement fit — no modifications required
- Covers 80, 90, and 115 HP Mercury 4-stroke outboards
- Also fits 2009–2010 Mercury 80 HP Jet Optimax
- Built for saltwater and freshwater marine environments
- Corrosion-resistant construction for long service life
- SKU: 57-5415
Parts Desk Insights
The 5415 is the go-to replacement when your Mercury 4-stroke is cranking slowly, clicking without turning over, or not engaging at all — and you’ve already confirmed the battery is good. Before pulling the starter, it’s worth testing the solenoid first, as a faulty solenoid is a common cause of no-crank symptoms and is a much less expensive fix. Compatible solenoid options include the Arco SW054 Mercury Solenoid (12V Isolated Base) and the Arco SW058HD Heavy-Duty Mercury Solenoid. For Mercury outboard starters in adjacent HP ranges, see the Arco 5392 for Mercury/Mariner 80–125 HP Inline 4-Cylinder — confirm your specific engine configuration and OEM part number to choose between the two.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.