Sierra 18-8533 Exhaust Manifold Mounting Kit

SKU: 4003142 - UPC: 808282127251 - MPN: 18-8533
$24.99 $32.29 ( / )

Available Stock : 4

Why Your Boat Needs a Reliable Exhaust Manifold Mounting Kit Picture this: you're out on the water, engine humming smoothly, when suddenly you notice a faint exhaust leak or unusual vibration. These issues often trace back to worn-out mounting hardware on the exhaust manifold. A high-quality kit like this restores...
Sierra Engine Parts
Same Day

Shipping (3PM)

Free Returns

Within 30 days

Sierra 18-8533 Exhaust Manifold Mounting Kit Product Description

Why Your Boat Needs a Reliable Exhaust Manifold Mounting Kit

Picture this: you're out on the water, engine humming smoothly, when suddenly you notice a faint exhaust leak or unusual vibration. These issues often trace back to worn-out mounting hardware on the exhaust manifold. A high-quality kit like this restores that tight, secure fit, preventing leaks that could lead to corrosion, overheating, or even catastrophic engine damage. Boat owners and mechanics swear by upgrading to durable replacements that stand up to saltwater exposure and constant vibration.

Investing in solid mounting hardware isn't just about fixing a problem—it's about peace of mind. It keeps exhaust gases contained, reduces noise, and maintains optimal engine performance for those long fishing trips or weekend cruises.

What's Included in This Exhaust Manifold Mounting Kit

This kit comes fully loaded with all the essentials for a straightforward replacement. You'll find precision-engineered stainless steel bolts designed for corrosion resistance, heavy-duty lock washers to combat loosening from engine vibes, hardened nuts for maximum torque retention, and often necessary gaskets or seals to ensure a leak-proof seal. Everything is crafted to OEM specifications, so you get that factory-fresh reliability without the premium price tag.

  • High-grade stainless steel bolts (typically M8 or M10 sizes, depending on engine)
  • Lock washers to prevent loosening over time
  • Matching nuts for secure fastening
  • Seals or gaskets for airtight installation

No more scavenging for mismatched parts—this kit has you covered for a complete overhaul.

Perfect Fit for Popular Marine Engines

Engineered for compatibility with a range of GM-based inboard and sterndrive setups, this kit slots right into V6 and V8 configurations commonly found in recreational boats. It pairs seamlessly with 4.3L, 5.0L, 5.7L, and similar blocks, making it a go-to for Mercruiser Alpha One, Bravo, and other popular outdrive systems. Always double-check your engine serial number against the manufacturer's cross-reference for the best match, but rest assured, it's built for broad marine application.

Whether you're maintaining a classic Chris-Craft or a modern pontoon, this hardware ensures your exhaust manifold stays rock-solid.

Step-by-Step Installation Guide for DIY Mechanics

Swapping out exhaust manifold mounts is a weekend warrior project that saves hundreds in shop labor. Here's a pro tip-filled walkthrough:

  1. Prep Work: Disconnect the battery, drain coolant if needed, and let the engine cool completely. Remove the old manifold carefully, noting torque specs.
  2. Clean Surfaces: Scrape off old gasket material and corrosion. A wire brush and solvent work wonders for a fresh start.
  3. Assemble Hardware: Slide lock washers onto bolts, thread nuts loosely, and position the manifold with new gaskets.
  4. Torque Down: Tighten in a crisscross pattern to 25-30 ft-lbs (consult your service manual for exact specs). Avoid over-torquing to prevent warping.
  5. Final Checks: Reconnect hoses, refill fluids, run the engine, and inspect for leaks with soapy water.

Pro Tip: Apply anti-seize to bolts for future ease, and inspect risers while you're in there—corrosion loves to hide.

Long-Term Maintenance Tips to Extend Kit Life

Once installed, a little TLC goes a long way. Annually inspect for looseness, especially after heavy use or saltwater exposure. Fresh water flush your engine after every outing, and consider dielectric grease on threads for extra protection. Spotting early signs like white exhaust smoke or manifold heat discoloration? Time for a check-up. Pair this with regular anode replacements to shield against electrolysis.

Boat enthusiasts know: Proactive care turns a good investment into a lifelong one.

Frequently Asked Questions

What engines is this exhaust manifold mounting kit compatible with?

It's designed for GM V6 and V8 marine engines, including many 4.3L to 5.7L setups in sterndrive applications. Verify with your engine model for the perfect fit.

Are the bolts stainless steel?

Yes, the bolts and hardware are made from corrosion-resistant stainless steel, ideal for harsh marine environments.

Do I need to replace the gaskets too?

The kit often includes gaskets or seals, but inspect your old ones. Replacing them ensures a leak-free seal and is highly recommended.

How do I know if my manifold mounts are failing?

Look for exhaust leaks, vibrations, coolant loss, or visible corrosion/rust around bolts. Early detection prevents bigger headaches.

What's the torque spec for installation?

Typically 25-30 ft-lbs in a star pattern, but always refer to your engine's service manual for precise torque values.

Can I install this kit myself?

Absolutely, with basic tools like sockets, torque wrench, and patience. It's a manageable DIY job for most boat owners.

How often should I replace exhaust manifold hardware?

Every 3-5 years in saltwater use, or sooner if you spot wear. Freshwater boats can go longer with proper maintenance.

Exhaust Manifold Mounting Kit



Save $7 when you buy the Sierra 18-8533 Exhaust Manifold Mounting Kit for only $24 from NVN Marine! Same day shipping before 3pm.

Sierra 18-8533 Exhaust Manifold Mounting Kit Technical Specifications

Type: 

Engine | Miscellaneous

Vendor: 

Sierra Engine Parts

Weight: 

1.08 lb

Sierra 18-8533 Exhaust Manifold Mounting Kit User Reviews

Sierra 18-8533 Exhaust Manifold Mounting Kit Shipping & Return

Shipping Weight: 

1.08 lb

Box Sizes: 

0.00 (h) x 7.00 (w) x 14.00 (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.

Sierra 18-8533 Exhaust Manifold Mounting Kit

$24.99 $32.29 ( / )