Mercury MerCruiser Quicksilver Closed-Cooling Exhaust Elbow Block-Off Gasket 8637251
In stock items ship same or next day.
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Product Description
Quicksilver 27-8637251 is the closed-cooling block-off gasket for specified MerCruiser center-rise exhaust manifolds. It separates the appropriate coolant passage at the manifold-to-exhaust-elbow joint.
Engine Compatibility
Mercury specifies this gasket for selected GM-based V6 and V8 MerCruiser sterndrive and inboard engines with center-rise outlet exhaust manifolds and MerCruiser closed cooling.
Alternate Part Numbers
Supersedes 27-863725. Older related references include 27-41811 and 27-860231.
Replacement and Installation
Inspect the manifold and elbow sealing faces when the joint is opened. Install the correct block-off gasket and follow the engine-specific exhaust service procedure.
Parts Desk Insight
Closed-cooling block-off gaskets are selected by the water-routing arrangement. A standard-cooling restrictor or full-flow gasket is a different part.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 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.