Trim Sender Limit Kit – Fits MerCruiser Alpha One Gen 2 & Bravo Stern Drives (Replaces 805320A03, 805320A1)
Trim Sender Limit Kit – Fits MerCruiser Alpha One Gen 2 & Bravo Stern Drives (Replaces 805320A03, 805320A1) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Product Details
This Trim Sender Limit Kit – Fits MerCruiser Alpha One Gen 2 & Bravo Stern Drives (Replaces 805320A03, 805320A1) is an essential component for ensuring accurate trim position feedback and setting tilt limits. It is engineered for a wide range of MerCruiser stern drives, including the MC-I, R, MR, Alpha One, Alpha One Gen II, and Bravo I, II, and III series, providing reliable performance for proper drive management.
This kit serves as a direct aftermarket replacement for MerCruiser part numbers 805320A03, 805320A1, 17693A2, and Sierra 18-7633, among others, ensuring a precise fit and function.
- Designed for direct, hassle-free installation on the gimbal housing.
- Features wire leads with pre-installed electrical connectors for a plug-and-play setup.
- The included Sierra part is backed by a limited lifetime warranty for peace of mind.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| MerCruiser | 805320A03 |
| MerCruiser | 805320A1 |
| MerCruiser | 17693A2 |
| MerCruiser | 63115A12 |
| MerCruiser | 88678A4 |
| MerCruiser | 88678A5 |
| MerCruiser | 96863A15 |
| Sierra | 18-7633 |
| Red Rhino | MR-971 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | OEM Part No. |
|---|---|---|
| MerCruiser | MC-I | 805320A03 |
| MerCruiser | R | 805320A03 |
| MerCruiser | MR | 805320A03 |
| MerCruiser | Alpha One | 805320A03 |
| MerCruiser | Alpha One Gen 2 | 805320A03 |
| MerCruiser | Bravo I | 805320A03 |
| MerCruiser | Bravo II | 805320A03 |
| MerCruiser | Bravo III | 805320A03 |
Technical Specs
- Product Type
- Trim Sender/Limit Switch Kit
- Installation
- Direct replacement
- Connection
- Wire leads with pre-installed electrical connectors
- Weight
- 0.72 lbs (0.33 kg)
- Fitting Type
- Direct mount to gimbal housing
- Warranty
- Limited lifetime (Sierra part)
- Other Technical Attributes
- Trim limit switch on port side; trim position sender on starboard side
What’s in the Box
- 1 x Trim Sender & Limit Kit (805320A03)
Installation Notes
- Disconnect the boat's battery to prevent electrical shorts.
- Raise the stern drive to the full "up" or "trailer" position for access.
- Locate the existing trim sender (starboard side) and limit switch (port side) on the gimbal housing.
- Carefully disconnect the wiring harnesses for both components.
- Unscrew and remove the old sender and limit switch, taking care not to drop hardware.
- Clean the mounting surfaces to ensure a good seal and proper contact.
- Mount the new trim sender and limit switch, ensuring they are correctly oriented.
- Securely fasten the components using the existing or supplied hardware.
- Reconnect the new wiring harnesses to the corresponding connectors.
- Reconnect the battery, then test the trim/tilt system to ensure the gauge reads correctly and the tilt limit functions properly.
Troubleshooting & FAQ
What are the signs of a failing trim sender or limit switch?
Common symptoms include an inaccurate or non-functional trim gauge, the drive trimming up but not down (or vice versa), or the inability to activate the "trailer" mode. Intermittent functionality is also a key indicator of wear or corrosion.
What is the difference between the trim sender and the trim limit switch?
The trim position sender (starboard side) relays the stern drive's angle to the trim gauge on your dashboard. The trim limit switch (port side) prevents the operator from trimming the drive up too far while underway, which could cause damage or unsafe handling. This kit includes both components.
Can I replace just one of the sensors?
Yes, but it is highly recommended to replace both the sender and the limit switch at the same time. They are exposed to the same wear and marine environment, and failure of one often precedes failure of the other. Replacing them as a kit is efficient and preventative maintenance.
Why is my trim gauge reading incorrectly after installation?
First, verify all wiring connections are secure and correct. Second, ensure the sender was installed in the correct orientation. If the problem persists, the sender may need to be calibrated according to your MerCruiser service manual's specific procedure to synchronize it with the gauge.
Is this kit compatible with all years of the listed MerCruiser models?
This kit fits a very wide range of the specified models (MC-I, Alpha One, Bravo series). However, we always recommend verifying your part number. Check the Part Number Matrix and compare our product photos against your existing part to ensure an exact match before ordering.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost?
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns?
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
Payment & Security
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