Aftermarket Transom Bellow Seal – Fits Volvo Penta 110S, 120S, MS25S, 130S & 150S (Replaces 21389074)
Aftermarket Transom Bellow Seal – Fits Volvo Penta 110S, 120S, MS25S, 130S & 150S (Replaces 21389074) is backordered and will ship as soon as it is back in stock.
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Aftermarket Transom Bellow Seal – Fits Volvo Penta 110S, 120S, MS25...
Aftermarket Transom Bellow Seal – Fits Volvo Penta 110S, 120S, MS25S, 130S & 150S (Replaces 21389074) is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket transom bellow seal is designed for Volvo Penta saildrive applications including the 110S, 120S, MS25S, 130S and 150S. It provides a replacement rubber sealing component at the saildrive-to-hull interface, helping protect the vessel from water ingress when correctly installed.
The product is listed for Volvo Penta reference number 21389074. Additional application reference numbers are shown below for identification and cross-reference only. Always compare the existing part, application and mounting arrangement before ordering.
- Product type: Transom bellow seal
- Application: Volvo Penta stern/outdrive and saildrive installations
- Function: Seals the transom or hull interface around the saildrive assembly
- Construction: Rubber sealing component
- Supply format: Single replacement bellow seal; additional hardware or separate external flaps are not specified as included
Part Number Matrix
These Volvo Penta numbers are listed as product application references. They are not a statement that every number represents a separate component included with this product.
| Brand | Reference Number | Reference Type |
|---|---|---|
| Volvo Penta | 21389074 | Primary application reference |
| Volvo Penta | 22303438 | Additional application reference |
| Volvo Penta | 21112450 | Additional application reference |
| Volvo Penta | 3840050 | Additional application reference |
| Volvo Penta | 3856597 | Additional application reference |
| Volvo Penta | 877362 | Additional application reference |
| Volvo Penta | 872026 | Additional application reference |
| Volvo Penta | 854934 | Additional application reference |
Engine & Model Compatibility
This listing covers the following Volvo Penta saildrive models. Model variants, production years and serial-number ranges are not separately specified, so confirm the exact unit before installation.
| Brand | Model | Application | Primary Reference |
|---|---|---|---|
| Volvo Penta | 110S | Saildrive / transom bellow seal | 21389074 |
| Volvo Penta | 120S | Saildrive / transom bellow seal | 21389074 |
| Volvo Penta | MS25S | Saildrive / transom bellow seal | 21389074 |
| Volvo Penta | 130S | Saildrive / transom bellow seal | 21389074 |
| Volvo Penta | 150S | Saildrive / transom bellow seal | 21389074 |
Technical Specs
- Product Type
- Transom bellow seal
- Brand Application
- Volvo Penta stern / outdrive
- Compatible Saildrives
- 110S, 120S, MS25S, 130S and 150S
- Installation Location
- Saildrive-to-hull or transom interface
- Material
- Rubber
- Primary Reference
- 21389074
- Product Format
- Single replacement sealing component
What’s in the Box
- 1 x Aftermarket transom bellow seal
Separate external flaps, mounting hardware, sealant and other service parts are not specified as included.
Installation Notes
- Haul the vessel out of the water and secure it safely before beginning work.
- Confirm that the existing saildrive and transom arrangement matches the listed Volvo Penta model.
- Disconnect or support associated components as required by the applicable Volvo Penta service procedure.
- Remove the old bellow seal and clean the mating surfaces thoroughly.
- Inspect the mounting area, retaining rings, fasteners and surrounding structure for corrosion, damage or distortion.
- Position the replacement bellow seal in the correct orientation and ensure it is fully seated.
- Use only the sealant, fasteners and tightening procedure specified by the applicable service manual.
- Reassemble the saildrive connection and check that the seal is not twisted, pinched or overstretched.
- Complete a careful leak inspection before returning the vessel to service.
Maintenance & FAQ
Which Volvo Penta models does this seal fit?
This listing covers Volvo Penta 110S, 120S, MS25S, 130S and 150S saildrive models. Confirm the exact model and physical part before ordering because year and serial-number coverage is not specified.
Is this a complete kit with an external rubber flap?
No separate external flap or additional component is specified as included for this product. The supply format is one replacement transom bellow seal. Check the contents of your original assembly and obtain any additional service parts separately if required.
What does reference number 21389074 identify?
21389074 is the primary Volvo Penta application reference listed for this aftermarket replacement. Other reference numbers appear in the part-number matrix for application identification and should be checked against your original part and saildrive model.
When should the bellow seal be inspected?
Inspect the rubber regularly for cracking, hardening, abrasion, distortion, swelling or signs of water leakage. Replace it immediately if deterioration or damage is found, and follow the maintenance interval and procedure specified for your saildrive.
Is this an OEM Volvo Penta part?
No. This listing is for an aftermarket replacement intended for the specified Volvo Penta applications. It is not sold as a genuine Volvo Penta component.
Can I install it without checking the original part?
No. Model names alone may not identify every installation variation. Compare the original bellow, mounting arrangement and reference numbers, and consult the applicable service documentation before installation.
Safety & Important Information
- Verify the saildrive model, original part and mounting arrangement before ordering.
- Do not rely on a model name alone when year or serial-number information is unavailable.
- A leaking or deteriorated saildrive bellow can allow water ingress and requires prompt attention.
- Professional installation is recommended because correct sealing and reassembly are safety-critical.
- This is an aftermarket replacement, not a genuine OEM Volvo Penta component.
About Sea Sierra
- Marine Parts Selection — Replacement components for common marine engine, sterndrive and saildrive applications.
- Application-Focused Listings — Product references and model coverage are provided to support part identification.
- Customer Support — Contact support with your original part details and equipment model if you need help confirming an application.
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