Sierra 18-1949 Manifold Riser Spacer
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Sierra 18-1949 Manifold Riser Spacer Product Description
Upgrading your marine engine's exhaust system starts with reliable components like the Sierra manifold riser spacer. Designed for durability in harsh saltwater conditions, this spacer creates a crucial barrier between the exhaust manifold and riser, minimizing galvanic corrosion that plagues many boat engines. Boat owners swear by it for extending the life of their powerplants without the hassle of constant replacements.
What sets this spacer apart? It's precision-engineered from high-grade materials that resist the brutal combo of heat, moisture, and electrolysis. Whether you're dealing with a weekend cruiser or a hardcore fishing rig, installing this piece ensures smoother exhaust flow and quieter operation under load.
Key Benefits for Your Marine Engine
- Corrosion Protection: Acts as an insulator to prevent direct metal-to-metal contact, slashing the risk of pitting and degradation in brackish or saltwater environments.
- Improved Performance: Promotes even exhaust gas distribution, potentially boosting engine efficiency and reducing backpressure for that extra throttle response.
- Easy Bolt-On Fit: Matches OEM specs for seamless integration—no custom machining or guesswork required during install.
- Long-Term Savings: Cuts down on frequent manifold and riser swaps, keeping your maintenance costs in check season after season.
- Vibration Dampening: Absorbs engine vibes, leading to less stress on gaskets and mounts over time.
Perfect Fit for Popular Engines
This Sierra spacer aligns with a range of inboard and sterndrive setups common in recreational boating. It's a go-to for engines from the 4.3L to larger V8 configurations, ensuring compatibility across various hull types from pontoons to center consoles. Always cross-check your engine's service manual for the exact match, but users report plug-and-play success on most mid-range powerplants.
Pro Tips for Installation
- Drain coolant and disconnect exhaust components to access the manifold area safely.
- Clean mating surfaces thoroughly—any debris can compromise the seal.
- Apply a marine-grade anti-seize to bolts for future ease of service.
- Torque to manufacturer specs (typically 20-25 ft-lbs) to avoid warping.
- Run a heat cycle test post-install to verify no leaks before hitting the water.
Most DIYers knock this out in under an hour with basic tools. Pro mechanics love it for quick winter layup prep.
Maintenance for Peak Performance
To maximize lifespan, inspect the spacer annually during haul-outs. Look for hairline cracks or discoloration, and pair it with fresh gaskets and risers for a full refresh. In high-use scenarios like charters, consider a zinc anode nearby to further shield against stray currents. Regular freshwater flushes after saltwater runs keep everything pristine.
Why Trust Sierra for Your Build
Sierra's reputation in the marine aftermarket isn't hype—it's battle-tested by thousands of captains from the Great Lakes to the Gulf. Their parts undergo rigorous testing for vibration, thermal cycling, and salt spray, often outperforming stock in real-world abuse. Choosing Sierra means backing your engine with components built to outlast the competition.
Frequently Asked Questions
What does a manifold riser spacer do?
It isolates the exhaust manifold from the riser, preventing galvanic corrosion by breaking electrical conductivity between dissimilar metals in wet environments.
Is this spacer compatible with my Mercury engine?
It fits many Mercury inboards and sterndrives in the 4.3L to 7.4L range—verify against your model year for best results.
How often should I replace the manifold riser spacer?
Every 3-5 years in saltwater use, or sooner if you spot corrosion during inspections.
Can I install this spacer myself?
Yes, with standard tools and about an hour of time. Follow torque specs to ensure a proper seal.
Does this spacer affect engine performance?
It can improve it by optimizing exhaust flow and reducing restrictions when paired with healthy manifolds and risers.
What material is the Sierra spacer made from?
Corrosion-resistant composite or phenolic material engineered for marine heat and moisture exposure.
Will this help with overheating issues?
Indirectly, by maintaining clear exhaust paths and preventing blockages from corrosion buildup.
Save $21 when you buy the Sierra 18-1949 Manifold Riser Spacer for only $174 from NVN Marine! Same day shipping before 3pm.
Sierra 18-1949 Manifold Riser Spacer Technical Specifications
| Type: | |
|---|---|
| Vendor: |
Sierra Engine Parts |
| Weight: |
7.64 lb |
| Replaces: |
- |
| Application: |
Chris-Craft, Crusader, Universal, Mercruiser & Volvo. Barr, Indmar and Marine Power Ford small block V8, 302-351 cid, GM small block V8 305-350 cid, GM big block C8, 454 cid. Use with manifold 19981, 19971, 1898 |
Sierra 18-1949 Manifold Riser Spacer User Reviews
Sierra 18-1949 Manifold Riser Spacer Shipping & Return
| Shipping Weight: |
7.64 lb |
|---|---|
| Box Sizes: |
5.00 (h) x 6.00 (w) x 10.00 (l) |
| Cubic Feet: |
300.0 |
| Returnable: |
Yes |
For detailed shipping policy please check our Shipping Policy and you can find our Return and Refund Policy here.