ARCO 12V Starter Solenoid for Mercury & MerCruiser – Isolated Base | SKU 57-SW054
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You have 30 days to request a return. All sale items are final sale.
ARCO 12V Starter Solenoid for Mercury & MerCruiser – Isolated Base
A direct-replacement 12-volt starter solenoid with an isolated base for Mercury outboard and MerCruiser stern-drive engines. The solenoid is the electrical switch that sends high-current power from the battery to the starter motor when you turn the key. When it fails, the engine won’t crank at all — or you’ll hear a single click with no starter engagement. This ARCO unit restores full starting function with a direct OEM-equivalent fit.
Features
- 12-volt, isolated base design
- Direct replacement for Mercury and MerCruiser starter solenoids
- OEM-equivalent fit — no wiring modifications required
- Replaces 5 Mercury OEM part numbers
- Built for reliable performance in marine electrical environments
Compatible Applications
- Replaces Mercury part numbers: 89-850189, 89-850189T, 89-91975, 89-96054, 89-96054T
- Mercury outboard engines using the above OEM references
- MerCruiser stern-drive engines using the above OEM references
Pairs Well With
- ARCO 12V Starter Solenoid for Mercury & MerCruiser (SW109) – alternative solenoid for Mercury/MerCruiser applications
- ARCO Starter Solenoid – MerCruiser, Cobra & Volvo Penta (SW450)
- ARCO Heavy-Duty Starter Solenoid (SW463)
- ARCO Outboard Starter Motor – Mercury / Force 90–120 HP Sport Jet
Parts Desk Insights
Best suited for Mercury outboard and MerCruiser owners where the engine won’t crank — particularly when you hear a single click from the solenoid area but the starter motor doesn’t spin. This is the isolated base version, which is required on engines where the solenoid mounting surface is not grounded to the engine block. Confirm your Mercury part number against the five listed above before ordering — Mercury used several solenoid variants, and the SW109 and SW450 are separate units for different applications.
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.