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26-32511A1 Upper Unit Seal Kit for Mercruiser Alpha One Gen I 1A 1B 1C EZ Shift MC-1 R MR | JLM Marine
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Upper Unit Seal Kit – Fits Mercruiser Alpha One Gen I, 1A, 1B, 1C, EZ Shift, MC-1, R, MR
This upper unit seal kit is engineered to fit Mercruiser sterndrive upper units including Alpha One Gen I, 1A, 1B, 1C, EZ Shift, MC-1, R, and MR models. Designed to restore proper sealing and performance, this kit is essential for maintaining your sterndrive's reliability and preventing water intrusion.
This seal kit directly replaces Mercury Marine/Quicksilver 26-32511A1, along with aftermarket equivalents GLM 87500 and Sierra Marine 18-2648, ensuring broad compatibility across sterndrive maintenance applications.
- Complete seal kit for upper unit service and rebuild
- Direct replacement for OEM and aftermarket part numbers
- Suitable for Mercruiser sterndrive applications
Part Number Cross-Reference
Use this table to confirm equivalent part numbers across OEM and aftermarket brands.
| Brand | Part Number |
|---|---|
| Mercury Marine/Quicksilver | 26-32511A1 |
| GLM | 87500 |
| Sierra Marine | 18-2648 |
Compatible Engine Models
Confirm your engine model/year in the table below.
| Brand | Model |
|---|---|
| Mercruiser | 1A |
| Mercruiser | 1B |
| Mercruiser | 1C |
| Mercruiser | EZ Shift |
| Mercruiser | MC-1 |
| Mercruiser | R |
| Mercruiser | MR |
| Mercruiser | Alpha One Gen I |
Technical Specifications
| Specification | Value |
|---|---|
| OEM Number | 26-32511A1 |
| Application | Upper Unit Seal Kit |
| Compatible Drive Type | Sterndrive |
Package Contents
This kit includes all necessary seals for upper unit service on compatible Mercruiser sterndrive models.
Installation Guide
- Disconnect the battery and remove the sterndrive unit from the boat following manufacturer procedures.
- Separate the upper unit from the lower unit by removing the retaining bolts.
- Carefully remove the old seals from the upper unit housing, taking note of their positions and orientations.
- Clean all seal surfaces thoroughly to remove old sealant, debris, and corrosion.
- Inspect seal grooves and shafts for wear, scoring, or damage that could compromise new seals.
- Lubricate the new seals with marine-grade grease before installation.
- Install each new seal carefully, ensuring proper orientation and seating in the grooves.
- Apply marine-grade sealant to mating surfaces as specified in your service manual.
- Reassemble the upper and lower units, torquing all fasteners to manufacturer specifications.
- Reinstall the sterndrive unit onto the boat and reconnect the shift and throttle cables.
- Refill the gear case with the correct type and quantity of gear lube, checking for leaks.
- Reconnect the battery and perform a functional test before returning to service.
Troubleshooting & FAQ
Q: How do I confirm this seal kit fits my Mercruiser sterndrive?
A: Verify your sterndrive model against the compatibility table above. This kit fits Alpha One Gen I, 1A, 1B, 1C, EZ Shift, MC-1, R, and MR models. Cross-reference your existing OEM part number (26-32511A1) with the numbers listed to ensure a proper match.
Q: What are the signs that my upper unit seals need replacement?
A: Common symptoms include gear oil leaking from the upper unit, water contamination in the gear oil (milky appearance), visible seal damage during inspection, or difficulty shifting. If you notice any of these issues, inspect and replace the seals promptly to prevent further damage.
Q: How often should I replace the upper unit seals?
A: Seal replacement intervals depend on usage and operating conditions. Inspect seals during annual maintenance or gear oil changes. Replace seals if you notice leaks, during upper unit rebuilds, or every 3-5 years as preventive maintenance in high-use applications.
Q: Can I install this seal kit myself or do I need a professional?
A: Installation requires mechanical aptitude, specialized tools, and knowledge of sterndrive systems. While experienced DIYers can perform this service with a proper manual and tools, professional installation is recommended to ensure correct assembly, torque specifications, and sealing.
Important Notes
- Verify that the product images and specifications match your original part.
- This product is an aftermarket replacement part and is not an OEM component.
- Professional installation is recommended to ensure safety and optimal performance.
We can ship to virtually any address in the world with free shipping available for most regions.
For our typical US and Canadian customers , our shipping timeframes are as follows:
- Amazon FBA: orders will be delivered within 1-5 business days after placing the order (during certain special periods such as major promotions, Christmas, etc., the delivery time of Amazon FBA may be affected).
- US warehouse shipment: orders will be delivered within 5 days after placing the order.
- China warehouse shipment: orders will be delivered about 12 days after placing the order.
When you place an order, we will estimate shipping and delivery dates for you based on the availability of your items and the shipping options you choose. Depending on the shipping provider you choose, shipping date estimates may appear on the shipping quotes page.
Please also note that the shipping rates for many items we sell are weight-based. The weight of any such item can be found on its detail page. To reflect the policies of the shipping companies we use, all weights will be rounded up to the next full pound.
Founded in 2002, JLM Marine has established itself as a dedicated manufacturer of high-quality marine parts, based in China. Our commitment to excellence in manufacturing has earned us the trust of top marine brands globally.
As a direct supplier, we bypass intermediaries, which allows us to offer competitive prices without compromising on quality. This approach not only supports cost-efficiency but also ensures that our customers receive the best value directly from the source.
We are excited to expand our reach through retail channels, bringing our expertise and commitment to quality directly to boat owners and enthusiasts worldwide.
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