Sierra 18-6823 Wiring Harness
Sierra 18-6823 Wiring Harness Product Description
Upgrading or repairing your outboard motor's tilt and trim system often runs into compatibility headaches, especially when swapping between different motor designs. The Sierra 18-6823 wiring harness steps in as a straightforward solution, bridging the gap between 3-wire tilt/trim motors and simpler 2-wire setups. Boat enthusiasts know the frustration of mismatched wiring— this adapter eliminates that hassle, letting you focus on smooth operation rather than electrical guesswork.
Why Choose This Wiring Harness for Your Boat?
Marine environments are tough on electrical components, with saltwater corrosion and constant vibration accelerating wear. This harness isn't just a patch; it's engineered for reliability in demanding conditions. Here's what sets it apart:
- Seamless Conversion: Transforms the control signals from a 3-wire motor (typically featuring up, down, and ground wires) to a 2-wire configuration (up/down combined), making it ideal for retrofits on popular outboard brands.
- Durable Construction: Built with marine-grade materials that resist UV exposure, moisture, and oil, ensuring long-term performance without frequent replacements.
- Easy Integration: No need for custom fabrication or soldering—plug-and-play design saves hours of labor, perfect for DIY boaters or weekend mechanics.
- Restores Full Functionality: Maintains precise tilt and trim control, preventing sluggish responses or erratic movements that compromise safety on the water.
Whether you're repowering an older rig or fixing a failed motor, this harness keeps your hydraulic system responsive, helping you trim efficiently for better planing and fuel economy.
Finding the Right Fit for Your Outboard
Compatibility is key in marine repairs. This harness works with a range of 3-wire tilt/trim motors commonly found on mid-range outboards from the 1980s through early 2000s. Check your motor's wiring diagram—look for three distinct leads from the tilt sender. It's a popular fix for models where factory 2-wire motors are scarce or pricey.
Quick Compatibility Checklist:
- Verify 3-wire setup: Red (up), blue/black (down), and black (ground).
- Matches standard 12V DC systems.
- Suits powerheads up to 150HP—always cross-reference with your service manual.
Pro tip: Before installation, inspect solenoid connections and relays. A faulty relay can mimic wiring issues, leading to unnecessary harness swaps.
Step-by-Step Installation Guide
Installing this harness takes under 30 minutes with basic tools. Follow these steps for a clean, professional result:
- Power Down: Disconnect the battery to avoid shorts.
- Access the Motor: Remove the cowling and locate the tilt/trim motor wiring at the transom bracket.
- Unplug Old Harness: Carefully disconnect the 3-wire plug from the motor and solenoid.
- Connect the Adapter: Plug the Sierra harness into the motor's 3-wire socket, then route the 2-wire output to your existing controls.
- Secure and Test: Use zip ties for strain relief, reconnect power, and cycle the trim in neutral to verify smooth up/down action.
Common pitfall: Reversed polarity—double-check colors against your diagram. If trim feels sluggish post-install, bleed the hydraulic system to remove air pockets.
Long-Term Maintenance for Peak Performance
To maximize lifespan, incorporate these habits into your routine:
- Rinse wiring connections with freshwater after every saltwater outing.
- Inspect for chafing annually, especially where harnesses flex during trim.
- Apply dielectric grease to plugs for corrosion protection.
- Monitor for overheating—could signal a drawing motor needing rebuild.
Boat owners report this harness outlasting OEM alternatives in harsh conditions, thanks to its robust insulation and connectors.
Frequently Asked Questions
What is the main function of the Sierra 18-6823 wiring harness?
It converts a 3-wire tilt/trim motor setup to a 2-wire design, simplifying wiring for compatible outboard systems and enabling easy motor swaps.
Is this harness suitable for all outboard motors?
No, it's designed for 3-wire tilt/trim motors on select 12V DC outboards. Always verify compatibility with your motor's wiring diagram.
How long does installation typically take?
Most users complete it in 20-30 minutes with basic tools. No soldering or modifications required.
What are the differences between 2-wire and 3-wire tilt/trim motors?
3-wire motors use separate up, down, and ground signals for precise control. 2-wire combines up/down into one reversible circuit, common in simpler systems.
Can this harness fix intermittent trim issues?
It resolves wiring mismatches but not mechanical failures like bad relays or hydraulics. Diagnose first for best results.
How do I maintain the wiring harness for saltwater use?
Rinse with freshwater after use, apply dielectric grease to connections, and inspect for wear during annual servicing.
Will this affect my boat's warranty?
As an aftermarket part, it shouldn't void engine warranties if installed correctly. Consult your manual or dealer.
Save $34 when you buy the Sierra 18-6823 Wiring Harness for only $85 from NVN Marine! Same day shipping before 3pm.
Sierra 18-6823 Wiring Harness Technical Specifications
| Type: | |
|---|---|
| Vendor: |
Sierra Engine Parts |
| Weight: |
0.38 lb |
| Fits: |
Universal |
Sierra 18-6823 Wiring Harness User Reviews
Sierra 18-6823 Wiring Harness Shipping & Return
| Shipping Weight: |
0.38 lb |
|---|---|
| Box Sizes: |
0.00 (h) x 0.00 (w) x 0.00 (l) |
| Cubic Feet: |
0.0 |
| Returnable: |
Yes |
For detailed shipping policy please check our Shipping Policy and you can find our Return and Refund Policy here.



