Mercury MerCruiser SeaCore Starboard Trim Cylinder Assembly — OEM 8M0128693 | Bravo One, Two, Three
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Mercury MerCruiser SeaCore Starboard Trim Cylinder Assembly — OEM 8M0128693 | Bravo One, Two, Three
This genuine OEM starboard power-trim cylinder is the SeaCore-configuration replacement for selected MerCruiser Bravo sterndrives. It forms the starboard side of the hydraulic trim system, working together with the port cylinder to raise, lower, and hold the sterndrive at the correct trim angle under hydraulic pressure. If the starboard side of your Bravo trim system is leaking, won’t hold trim position, or has a damaged rod or cylinder body, 8M0128693 is the OEM replacement — but confirming SeaCore configuration is critical before ordering.
Part Information
- OEM Part Number: 8M0128693
- Brand: Mercury / MerCruiser
- Official Product Type: Starboard hydraulic power-trim cylinder assembly
- Configuration: SeaCore
- Position: Starboard (right side)
- Supersedes: 8M0108282, 866464A02
- Matching Port Cylinder: 8M0128692 (SeaCore port side)
- System: Hydraulic power-trim system
- Quantity: One starboard cylinder per trim assembly
- GTIN / UPC: 745061776890
Compatible Applications
- MerCruiser Bravo One — SeaCore trim-cylinder configuration
- MerCruiser Bravo Two — SeaCore trim-cylinder configuration
- MerCruiser Bravo Three — SeaCore trim-cylinder configuration
- MerCruiser Bravo X One / Two / Three — SeaCore configuration
- MerCruiser Bravo XR One / Three — SeaCore configuration
- MerCruiser Bravo XR SportMaster — SeaCore configuration
- Selected high-performance and integrated transom applications using this SeaCore starboard cylinder
- Important: Confirm the drive model, transom assembly, and trim-cylinder configuration before ordering — standard Bravo systems use a different starboard trim cylinder; see 8M0132610 for the standard (non-SeaCore) starboard cylinder
Related Parts
- Mercury MerCruiser Bravo Trim Cylinder Assembly Starboard — 8M0132610 (standard non-SeaCore version)
When to Replace
- Hydraulic fluid leaking from the cylinder body, rod seal, or fitting connections
- Sterndrive will not hold trim position and diagnosis points to cylinder failure
- Cylinder rod is bent, scored, or corroded beyond service limits
- Cylinder body is cracked or physically damaged
- Internal cylinder wear causing erratic or weak trim operation
Installation Notes
- Inspect hydraulic hoses, fittings, mounting pins, anodes, and mating hardware while the cylinder is removed
- Replace hoses and seals as needed rather than reusing worn components
- Follow the applicable Mercury service procedure for cylinder installation and hydraulic-system bleeding
- Verify smooth, full-range trim operation and check for fluid leakage before returning the drive to service
- Torque all hydraulic fittings to Mercury specification to prevent leaks under pressure
Technical FAQ
What is the difference between SeaCore and standard Bravo trim cylinders?
Mercury’s SeaCore configuration uses a corrosion-protection package designed for saltwater environments, including specific cylinder materials and coatings. Standard Bravo drives use a different starboard cylinder (8M0132610). The two are not interchangeable — always confirm whether your transom assembly is SeaCore or standard before ordering.
What part numbers did 8M0128693 supersede?
8M0128693 is the current OEM replacement for 8M0108282 and 866464A02. If you have been ordering either of those numbers, 8M0128693 is the updated part.
Does this listing include the port cylinder?
No. This listing is for the starboard (right-side) cylinder only. The matching SeaCore port-side cylinder is 8M0128692. Both cylinders are typically replaced together when servicing a hydraulic leak or major trim system overhaul.
Parts Desk Insights
The most common ordering error on Bravo trim cylinders is not confirming SeaCore vs. standard — both configurations are listed in Mercury’s catalog for the same drive models, and the part numbers look similar. The most reliable way to confirm is to check the existing cylinder part number or match the transom assembly number. It’s also worth noting that trim cylinders rarely fail in isolation — if one side is leaking, inspecting the hoses, fittings, and port cylinder at the same time often prevents a repeat visit. Browse the full MerCruiser Marine Engine Parts collection for related sterndrive components.
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.