SIERRA 18-04761 Riser Block Off Gasket | Marine Exhaust Seal
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
The SIERRA Riser Block Off Gasket - is designed to provide a dependable seal when an exhaust riser is removed, blocked off, or temporarily taken out of service. It helps protect marine engines from water intrusion, exhaust leaks, debris entry, and corrosion during winterization, rebuilds, riser replacement, or service work.
Precision-cut for proper riser port sealing, this gasket is made from durable marine-grade compressed gasket material suitable for demanding exhaust environments.
Key Features
- Precision-cut riser block off gasket
- Helps prevent water ingestion into the engine
- Reduces risk of exhaust gas leaks
- Useful during winterization, rebuilds, and riser service
- Marine-grade compressed gasket construction
- Designed for inboard and sterndrive exhaust applications
- New replacement gasket
Specifications
- SKU: 47-04761
- Brand: SIERRA
- Type: Riser Block Off Gasket
- Material: Marine-grade compressed gasket material
- Condition: New
- Application: Marine exhaust riser block-off sealing
Compatibility & Fitment
Designed for compatible marine inboard and sterndrive exhaust riser applications using SIERRA 18-04761. Always verify fitment by comparing your existing gasket, riser port shape, engine model, and manufacturer part number before installation.
Installation Notes
Clean and inspect all mating surfaces before installation. Check for corrosion, warping, pitting, or old gasket residue. Install using manufacturer-recommended torque specifications. Replace the gasket each time the riser is removed to ensure a reliable seal.
Maintenance Tips
Inspect riser and manifold sealing surfaces during seasonal service. Replace worn, crushed, or heat-damaged gaskets immediately. Keep spare gaskets on hand for winterization and exhaust system maintenance.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.