Transom Sealing Kit – Fits Volvo Penta DP-S, DP-SM, SX-M & SX-C (Replaces 3858631, 3854270)
Transom Sealing Kit – Fits Volvo Penta DP-S, DP-SM, SX-M & SX-C (Replaces 3858631, 3854270) 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).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Transom Sealing Kit – Fits Volvo Penta DP-S, DP-SM, SX-M & SX-C...
Product Details
This aftermarket Transom Sealing Kit is designed for a range of Volvo Penta sterndrive models, including the DP-S, DP-SM, SX-M, and SX-C series. It provides a reliable seal to protect the transom assembly from water intrusion, ensuring the integrity and longevity of your sterndrive system.
It serves as a direct replacement for Volvo Penta OEM part numbers 3858631 and 3854270, offering a precise fit and restoring original performance.
- Engineered as a direct replacement for original equipment for a straightforward installation.
- Kit includes the essential transom shield gasket and seal assembly.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Volvo Penta | 3858631 |
| Volvo Penta | 3854270 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | OEM Part No. | Notes |
|---|---|---|---|
| Volvo Penta | DP-S | 3858631 | Transom Shield |
| Volvo Penta | DP-S1 | 3858631 | Transom Shield |
| Volvo Penta | DP-SM | 3858631 | Transom Shield |
| Volvo Penta | SX-M | 3858631 | Transom Shield |
| Volvo Penta | SX-C | 3858631 | Transom Shield |
| Volvo Penta | SX-S | 3858631 | Transom Shield |
Technical Specs
- Product Type
- Transom Sealing Kit
- Installation
- Direct replacement for original equipment
- Fitting Type
- Transom shield gasket & seal assembly
- Dimensions
- 35.0" L x 25.0" W x 6.0" H
- Other Technical Attributes
- Special Order Item in some retailers
What’s in the Box
- 1 x Transom Sealing Kit (Replaces 3858631/3854270)
Installation Notes
- Ensure the engine is off and the battery is disconnected before starting work.
- Carefully remove the sterndrive unit according to the manufacturer's service manual.
- Remove the old transom seal and any remaining gasket material or sealant fragments.
- Thoroughly clean and inspect the mounting surfaces on the transom and shield. Ensure they are dry and free of corrosion or debris.
- Carefully position the new seal and gasket assembly. Do not use excessive force.
- Apply a marine-grade sealant if specified by your service manual.
- Reinstall the sterndrive unit, torquing all bolts to the manufacturer's specifications.
- Reconnect the battery and test the engine in the water, carefully checking for any leaks around the transom.
Troubleshooting & FAQ
How do I confirm this kit fits my specific sterndrive model?
This kit fits various Volvo Penta DP-S, DP-SM, SX-M, and SX-C models. Please review the "Engine & Model Compatibility" table and cross-reference the OEM part number 3858631 with your service manual to ensure an exact match.
What are the common signs of a failing transom seal?
The most common sign is water entering the bilge area from the transom assembly. You may also notice corrosion around the inner transom plate or hear unusual noises from the area while underway, indicating movement and a potential loss of seal integrity.
How often should a transom seal be replaced?
There is no fixed interval, but transom seals should be inspected regularly as part of routine maintenance. It is recommended to replace them preventatively every 5-7 years, or immediately if you notice any signs of leaks, cracking, or deterioration.
Is this a complete kit for the transom seal replacement?
This kit contains the primary seal and gasket assembly (replaces OEM 3858631/3854270) needed for the job. However, depending on your specific situation, you may require additional sealant or hardware, which are not included.
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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