Outdrive Mounting Gasket Set for OMC Cobra and Volvo Penta SX Sterndrives
Outdrive Mounting Gasket Set for OMC Cobra and Volvo Penta SX Sterndrives is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
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Outdrive Mounting Gasket Set for OMC Cobra and Volvo Penta SX Stern...
Outdrive Mounting Gasket Set for OMC Cobra and Volvo Penta SX Sterndrives is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket outdrive mounting gasket set is designed for the sealing interface between compatible OMC Cobra sterndrives or Volvo Penta SX-series drives and the transom assembly. It is intended for service or replacement when the drive unit is removed and the original sealing components should not be reused.
Commonly listed replacement references include OMC 508105, 915840, and 0911836; Volvo Penta 3852560, 3852565, 911823, and 911851; Sierra 18-2613; GLM 39630; and Mallory 9-62605. Always compare the original gasket and confirm the exact drive application before ordering.
- Replacement gasket set for compatible OMC Cobra and Volvo Penta SX sterndrives.
- Designed to restore sealing at the drive-to-transom mounting interface.
- Includes the gasket, seal, and O-rings listed below.
- Suitable for service replacement when the sterndrive is removed.
Part Number Matrix
The following references are provided for cross-reference purposes. Part-number listings do not replace confirmation of the drive model, transom assembly, and gasket shape.
| Brand | Part Number |
|---|---|
| OMC | 508105 |
| OMC | 915840 |
| OMC | 0915840 |
| OMC | 0508105 |
| OMC | 0911836 |
| Volvo Penta | 3852560 |
| Volvo Penta | 3852565 |
| Volvo Penta | 911823 |
| Volvo Penta | 911851 |
| Sierra | 18-2613 |
| GLM | 39630 |
| Mallory | 9-62605 |
Compatibility
This gasket set is commonly listed for OMC Cobra sterndrives from approximately 1986–1993 and for selected Volvo Penta SX-family applications. Compatibility depends on the specific drive and transom assembly rather than engine horsepower alone.
| Brand | Drive family | Application notes | Common reference |
|---|---|---|---|
| OMC | Cobra sterndrive | Commonly listed for compatible 1986–1993 Cobra transom and drive assemblies | 508105 / 915840 |
| Volvo Penta | SX-S, SX-C, SX-R, SX-M, and selected DP-S applications | Confirm the gasket profile and transom assembly before installation | 3852560 / 3852565 |
Technical Specs
- Product Type
- Outdrive/Sterndrive Mounting Gasket Set
- Installation Location
- Between the compatible sterndrive or gear housing mounting interface and transom assembly
- Installation
- Replacement installation; follow the applicable manufacturer service manual
- Material
- Aftermarket sealing materials selected for the listed marine service application
- Weight
- Approximately 0.14 lb (0.06 kg)
What's in the Box
- 1 x Outdrive mounting gasket
- 1 x Outdrive seal
- 2 x O-rings
Installation Notes
- Disconnect the battery and make sure the engine is switched off and cool.
- Remove the sterndrive unit from the transom shield according to the applicable manufacturer's service manual.
- Remove the old gasket, seal, and O-rings. Clean both mating surfaces thoroughly and remove old gasket material, dirt, and corrosion.
- Inspect the mating surfaces for pitting, distortion, or damage that could prevent a proper seal.
- Position the replacement gasket, seal, and O-rings in their correct locations. Do not force or stretch the sealing components.
- Reinstall the sterndrive unit and verify that it is correctly aligned with the transom assembly.
- Torque the mounting fasteners in the manufacturer's specified sequence and to the specified values.
- Check for leaks after assembly and before returning the vessel to normal operation.
Troubleshooting & FAQ
How do I know if the outdrive mounting gasket is failing?
Possible signs include water entering the bilge from the transom area, moisture around the drive mounting interface, corrosion near the mounting fasteners, or visible deterioration of the gasket after the drive is removed. Inspect the complete transom assembly before replacing the gasket.
Is this gasket compatible with both OMC Cobra and Volvo Penta SX drives?
It is commonly listed for compatible OMC Cobra and Volvo Penta SX-family sterndrives. Drive and transom variations exist, so confirm the original part number, gasket profile, and exact drive application before ordering.
When should the gasket be replaced?
Replace it whenever the sterndrive is removed and the sealing interface is disturbed, or whenever the existing gasket shows damage, compression loss, deterioration, or leakage.
Does this set include sealant?
No. Sealant is not included. Use sealant only when required by the applicable service manual; some gasket applications are designed for installation on clean, dry mating surfaces.
Can I reuse the old gasket, seal, or O-rings?
No. These sealing components are intended for replacement during service. Reusing compressed or damaged components can cause leaks and may lead to water intrusion or corrosion.
Is this an OEM part?
No. This is an aftermarket replacement gasket set intended for the listed applications. OMC, Volvo Penta, Sierra, GLM, and Mallory references are used for identification and cross-reference only.
What should I verify before ordering?
Compare the original gasket, confirm the drive and transom assembly, check the applicable model and year information, and verify the listed replacement reference. Contact a qualified marine technician if the application is uncertain.
Shipping speed and cost
Shipping methods, delivery estimates, and costs are shown at checkout and may vary by destination and service availability.
Warranty and returns
Warranty coverage and return eligibility are governed by the current store policies. Keep the order information and return the item unused and in its original condition when required by the applicable policy.
Safety & Important Information
- Verify the gasket profile, original part number, drive model, and transom application before purchase.
- This is an aftermarket replacement, not an original equipment component.
- Follow the applicable service manual for removal, installation, fastener torque, alignment, and sealant requirements.
- Professional installation is recommended if you are not experienced with sterndrive service.
About Sea Sierra
- Marine Replacement Parts — We supply aftermarket marine components for practical service and repair applications.
- Application-Focused Support — Compare part numbers and application details before ordering to help ensure the correct fit.
- Value-Oriented Products — Replacement parts are selected for dependable fit and service use at a practical price.
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