MerCruiser Seal Kit 98421A1 - Genuine OEM Marine Engine Service Kit
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Genuine MerCruiser OEM seal kit engineered for precision fit and reliable sealing in marine engine and drive assemblies. This factory-specification service kit includes all necessary seals and gaskets for proper assembly, ensuring leak-free operation, optimal performance, and long-term durability in demanding marine environments.
Key Features:
- Genuine MerCruiser OEM service kit - factory quality and fit
- Complete seal and gasket set for specific application - no additional parts needed
- Precision-manufactured to exact tolerances for proper sealing surfaces
- Marine-grade materials engineered to resist oil, fuel, coolant, and saltwater
- Temperature and pressure-rated for marine engine operating conditions
- Factory-tested for dimensional accuracy and material compatibility
- Essential components for leak-free engine and drive assembly
- Direct replacement for worn, damaged, or aged seals
Technical Specifications:
- Part Number: 98421A1
- Manufacturer: MerCruiser (Mercury Marine)
- Application: MerCruiser Marine Engines and Sterndrives
- Material: Marine-grade elastomers, rubber compounds, and gasket materials
- Type: Seal kit (complete service set)
- Temperature Range: Engineered for marine engine operating temperatures
- OEM Quality: Factory specification
- Kit Contents: Multiple seals and gaskets as specified for application
Function and Importance:
Seals and gaskets are critical components that prevent fluid leakage, maintain system pressure, and protect internal components from contamination. They create leak-proof barriers between mating surfaces, compensate for surface irregularities, and maintain their sealing properties under thermal cycling, vibration, and pressure fluctuations. Worn or damaged seals can cause oil leaks, coolant loss, air infiltration, reduced performance, and potential engine damage. Using complete OEM seal kits ensures all sealing surfaces are properly renewed during service or rebuild operations.
Maintenance and Replacement:
Always replace seals during disassembly and reassembly operations. Never reuse seals or gaskets, as they compress and conform to mating surfaces and cannot provide reliable sealing when reinstalled. Inspect mating surfaces for damage, corrosion, or warping before installation. Clean surfaces thoroughly and apply sealant or lubricant only as specified in factory service procedures. Always use genuine OEM seal kits to ensure proper material specifications, dimensional accuracy, and chemical compatibility. Follow factory torque specifications and assembly sequences for optimal sealing performance.
Compatibility:
Designed for specific MerCruiser engine and sterndrive applications. Verify part number compatibility with your engine model and serial number before ordering. Consult factory service manuals or authorized dealers for application-specific fitment information, installation procedures, and torque specifications.
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.