Sierra 18-2671 985612 OMC Seal Kit
Sierra 18-2671 985612 OMC Seal Kit Product Description
Why Choose the Sierra 18-2671 OMC Seal Kit for Your Outboard Motor?
Keeping your OMC outboard engine running smoothly starts with reliable seals that prevent leaks and protect vital components. The Sierra 18-2671, a direct replacement for OMC 985612, delivers OEM-level performance at an aftermarket value. Crafted from high-grade materials, this seal kit tackles common issues like oil seepage and water intrusion, ensuring your engine's longevity on the water.
Boat owners and mechanics trust Sierra parts for their precision fit and durability. Whether you're prepping for a season of fishing or routine maintenance, this kit restores factory sealing integrity without the hassle of sourcing originals.
Perfect Fit for Popular OMC Models
Designed specifically for OMC engines, the Sierra 18-2671 seal kit matches the 985612 specifications seamlessly. It suits a range of Johnson and Evinrude outboards, including V4, V6, and inline models from various horsepower classes. Always cross-check your engine's serial number for exact compatibility, but this kit shines in mid-range powerheads where crankshaft and gearcase seals wear fastest.
- Replaces OMC 985612 with identical dimensions and materials
- Ideal for engines prone to seal degradation from saltwater exposure
- Supports both freshwater and marine environments
Key Features and Benefits
This OMC seal kit isn't just a replacement—it's an upgrade in reliability. Each seal undergoes rigorous testing for heat resistance, flexibility, and pressure tolerance, mimicking the demands of high-RPM operation.
Durable Construction
Viton and nitrile compounds resist fuels, oils, and corrosion for extended service life.
Easy Installation
Pre-sized for drop-in replacement; minimal tools required beyond standard engine service gear.
Leak Prevention
Eliminates drips that lead to low oil levels, overheating, and costly repairs.
Cost-Effective Maintenance
Extend engine intervals and avoid premature rebuilds with proactive seal swaps.
Signs Your OMC Engine Needs a New Seal Kit
Spotting seal failure early saves your powerhead. Watch for milky oil from water contamination, visible drips under the cowling, or unusual gear lube loss. Harsh vibrations or smoke from the exhaust can signal deeper issues tied to compromised seals. Regular inspections during oil changes catch these problems before they escalate.
Pro tip: Flush your engine thoroughly after every saltwater trip to prolong seal life and maintain peak performance.
Installation Tips for Sierra 18-2671
Swap in the Sierra 18-2671 during your next lower unit service for best results. Clean mating surfaces meticulously, apply a thin layer of marine grease to lips, and torque to spec. Pair with fresh gear lube and impeller checks for a complete refresh. If you're new to outboard work, reference your service manual's torque values—precision matters here.
- Drain fluids and remove necessary covers
- Extract old seals with a proper puller
- Install new seals with a driver tool
- Reassemble, refill, and test run
"Switched to Sierra seals on my '85 Evinrude—ran like new after two seasons of hard use." – Experienced boater feedback.
Frequently Asked Questions
What does the Sierra 18-2671 seal kit replace?
It directly replaces OMC part number 985612, providing an identical fit for compatible OMC outboard engines.
Is the Sierra 18-2671 suitable for saltwater use?
Yes, its corrosion-resistant materials make it ideal for both freshwater and saltwater environments, extending service life in harsh conditions.
How do I know if my OMC engine needs this seal kit?
Look for oil leaks, water in the oil (milky appearance), or low gear lube levels—these are classic signs of seal wear.
Can I install the Sierra 18-2671 myself?
Absolutely, with basic tools and mechanical knowledge. Clean surfaces well and follow torque specs for best results.
What engines is the 18-2671 compatible with?
It fits many Johnson and Evinrude V4, V6, and inline OMC models—verify with your engine's serial number for precision.
How long do these seals typically last?
With proper maintenance, expect 2-5 years or 300-500 hours, depending on usage and water conditions.
Does this kit include all necessary seals?
Yes, it's a complete kit covering crankshaft, propeller shaft, and related seals as per OMC 985612 specs.
Save $5 when you buy the Sierra 18-2671 985612 OMC Seal Kit for only $36 from NVN Marine! Same day shipping before 3pm.
Sierra 18-2671 985612 OMC Seal Kit Technical Specifications
| Type: | |
|---|---|
| Vendor: |
Sierra Engine Parts |
| Weight: |
0.19 lb |
Sierra 18-2671 985612 OMC Seal Kit User Reviews
Sierra 18-2671 985612 OMC Seal Kit Shipping & Return
| Shipping Weight: |
0.19 lb |
|---|---|
| Box Sizes: |
0.00 (h) x 7.00 (w) x 9.00 (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.



