Sierra 18-2799 Yamaha Lower Unit Seal Kit
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Sierra 18-2799 Yamaha Lower Unit Seal Kit Product Description
Leaky lower units can turn a peaceful day on the water into a frustrating ordeal, with gear oil seeping out and water sneaking in. The Sierra 18-2799 Yamaha lower unit seal kit steps in as your reliable fix, restoring watertight integrity to your outboard's gearcase. Crafted for boaters who demand performance without compromise, this kit tackles the wear from constant submersion, saltwater exposure, and high-RPM operation that plagues Yamaha lower units over time.
Engineered for Long-Lasting Protection
Unlike basic replacements that fail prematurely, Sierra's design prioritizes durability with high-grade materials resistant to oil, fuel, and corrosion. This means fewer rebuilds and more time fishing or cruising. Boaters report smoother shifts and quieter operation post-install, as fresh seals eliminate the slop that leads to accelerated gear wear. It's the smart choice for proactive maintenance, catching issues before they cascade into costly overhauls.
Comprehensive Coverage for Your Yamaha Gearcase
This all-in-one kit equips you with every seal needed to refresh the lower unit's critical points: propeller shaft, driveshaft housing, shift rod, and more. Precision-molded components ensure a snug fit, mimicking OEM specs while outperforming in harsh marine environments. Whether you're addressing a slow drip from the prop shaft or prepping for a full gear lube change, it covers the bases without guesswork.
- Propeller shaft seals to stop oil leaks at the business end
- Driveshaft and water pump seals for upper integrity
- Shift shaft and rod seals for precise control
- Universal gaskets to tie it all together
Real-World Applications and Fixes
Picture this: your Yamaha outboard starts whining under load, or you spot milky gear oil from water intrusion. These are hallmarks of degraded seals, often hitting harder after trailering mishaps or neglected service intervals. The Sierra 18-2799 shines here, commonly used on mid-range horsepower models where downtime hurts most. It's a staple for weekend warriors rebuilding after a grounding or pros servicing rental fleets, proving its mettle across freshwater lakes to coastal bays.
DIY Installation Made Straightforward
No need for a marine yard lift—most installs happen dockside with basic tools. Start by draining the gear lube, then methodically pull the lower unit. Clean mating surfaces meticulously to avoid contamination, and use marine-grade sealant sparingly on gaskets. Torque specs from your service manual are key; overtightening warps seals. Refill with fresh lube and run a test—quiet gears and clean props confirm success. For novices, pair it with a gear lube pump for mess-free results.
Prolong Your Outboard's Prime with Smart Habits
Pair this seal kit with routine checks: inspect for prop dings quarterly, change lube annually or every 100 hours, and flush after saltwater runs. These steps amplify the kit's impact, staving off the "one leak leads to three" cycle. Savvy owners swear by it for extending lower unit life beyond factory expectations, keeping resale value high and adventures uninterrupted.
Frequently Asked Questions
What is a lower unit seal kit and why do I need one for my Yamaha outboard?
A lower unit seal kit replaces the rubber seals and gaskets in your outboard's gearcase that prevent gear oil from leaking out and water from entering. Over time, they crack from heat, pressure, and corrosion, leading to lubrication loss and potential gear damage. Installing one restores protection and prevents expensive repairs.
Is the Sierra 18-2799 compatible with all Yamaha outboards?
It's designed for specific Yamaha models—consult the Sierra catalog or cross-reference your engine's serial number for exact fitment. It covers popular mid-horsepower gearcases where seal kits are a common service item.
How do I know if my lower unit needs new seals?
Signs include gear oil spots under the boat, milky lube from water mix, unusual noise during shifts, or visible drips from the prop shaft or drain plug. A pressure test or simple visual check during lube changes confirms it.
Can I install the Sierra 18-2799 myself without special tools?
Yes, with standard tools like sockets, seal pullers, and a torque wrench. Drain the lube first, follow a service manual, and take your time on cleaning. It's a 2-4 hour job for DIYers with mechanical aptitude.
What maintenance follows installing a new lower unit seal kit?
Change gear lube after 5-10 hours of run time to seat the seals, then annually. Check props for damage regularly and avoid over-revving during break-in to maximize longevity.
How does Sierra quality compare to OEM Yamaha parts?
Sierra meets or exceeds OEM standards with robust materials suited for marine abuse. Boaters often find it more resilient in saltwater, at a fraction of dealer costs, backed by proven field performance.
Will this kit fix water in the gear oil?
It addresses seal-related intrusion but won't fix damaged gears or bearings. Drain and inspect first—if water's present without metal shavings, seals are likely the culprit.
Save $35 when you buy the Sierra 18-2799 Yamaha Lower Unit Seal Kit for only $110 from NVN Marine! Same day shipping before 3pm.
Sierra 18-2799 Yamaha Lower Unit Seal Kit Technical Specifications
| Type: | |
|---|---|
| Vendor: |
Sierra Engine Parts |
| Weight: |
0.48 lb |
| Description: |
Lower Unit Seal Kit: Yamaha L225-L250 |
| Replaces: |
61A-W0001-21-00, |
Sierra 18-2799 Yamaha Lower Unit Seal Kit User Reviews
Sierra 18-2799 Yamaha Lower Unit Seal Kit Shipping & Return
| Shipping Weight: |
0.48 lb |
|---|---|
| Box Sizes: |
1.00 (h) x 10.00 (w) x 13.00 (l) |
| Cubic Feet: |
130.0 |
| Returnable: |
Yes |
For detailed shipping policy please check our Shipping Policy and you can find our Return and Refund Policy here.