Gear Housing to Pivot Gasket – Fits OMC Cobra Stern Drive 2.3L-5.8L (Replaces 915840, 911836)
Gear Housing to Pivot Gasket – Fits OMC Cobra Stern Drive 2.3L-5.8L (Replaces 915840, 911836) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
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Gear Housing to Pivot Gasket – Fits OMC Cobra Stern Drive 2.3L-5.8L...
Product Details
This Gear Housing to Pivot Gasket is designed for OMC Cobra stern drives, fitting a wide range of engines from 1986 to 1993. It's compatible with 2.3-3.0L 4-cylinder (85-130 HP), 4.3L V6 (160-165 HP), and 5.0-5.8L V8 (185-240 HP) models, ensuring a precise seal between the gear housing and pivot connection.
It serves as a direct replacement for OMC part numbers 915840, 0915840, 911836, and 0911836, and interchanges with Sierra 18-2918, GLM 34730, Mallory 9-62650, and Barr OMC47-911836.
- Engineered for direct replacement and easy installation.
- Seals the gear housing to the pivot connection to prevent leaks.
- Constructed from a durable paper/composite material for a reliable fit.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| OMC | 915840 / 0915840 |
| OMC | 911836 / 0911836 |
| Sierra | 18-2918 |
| GLM | 34730 |
| Mallory | 9-62650 |
| Barr | OMC47-911836 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For OMC applications, this gasket fits various Cobra stern drive models produced between 1986 and 1993.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| OMC | Cobra Stern Drive | 85-130 | 4-Stroke | 1986–1993 | 915840 | 2.3-3.0L 4-cylinder engines |
| OMC | Cobra Stern Drive | 160-165 | 4-Stroke | 1986–1993 | 915840 | 4.3L V6 engines |
| OMC | Cobra Stern Drive | 185-240 | 4-Stroke | 1986–1993 | 915840 | 5.0-5.8L V8 engines |
| OMC | Cobra 2.5L | 120 | 4-Stroke | 1986 | 915840 | |
| OMC | Cobra 5.7L | 230 | 4-Stroke | 1987 | 915840 | |
| OMC | Cobra 2.3L | 100 | 4-Stroke | 1987–1990 | 915840 | |
| OMC | Cobra 3.0L | 130 | 4-Stroke | 1988 | 915840 | |
| OMC | Cobra 5.0L | 200 | 4-Stroke | 1988 | 915840 | |
| OMC | Cobra 4.3L | 175 | 4-Stroke | 1989–1990 | 915840 | |
| OMC | Cobra 5.8L | 240 | 4-Stroke | 1989 | 915840 | |
| OMC | Cobra 4.3L | 185 | 4-Stroke | 1991 | 915840 | |
| OMC | Cobra 5.0L | 200 | 4-Stroke | 1993 | 915840 | |
| OMC | Stern Drive 584APLAMH | 230-240 | 4-Stroke | 1992 | 915840 | 5.8L V8 |
Technical Specs
- Product Type
- Gear Housing to Pivot Gasket
- Installation
- Direct replacement
- Housing Material
- Paper/Composite
- Housing Color
- Black
- Dimensions
- 29 x 19 cm (approx. 11.4 x 7.5 inches)
- Weight
- 0.11 kg (0.25 lbs)
- Warranty
- Varies by seller (typically 1 year against manufacturing defects)
- Other Technical Attributes
- Used to seal the gear housing to pivot connection in OMC Cobra stern drives
What’s in the Box
- 1 x Gear Housing to Pivot Gasket (915840/0915840)
Installation Notes
- Disconnect the battery and follow all manufacturer safety precautions.
- Drain the gearcase lubricant completely into an approved container.
- Carefully disassemble the components required to access the gear housing to pivot connection.
- Remove the old gasket and thoroughly clean both mating surfaces. Ensure they are free of old gasket material, sealant, oil, and debris.
- Position the new gasket correctly onto the cleaned surface.
- Reassemble the stern drive components, tightening bolts to the manufacturer's specified torque in the correct sequence.
- Refill the gearcase with the recommended lubricant to the proper level.
- After reassembly, check for any leaks around the new gasket before and after running the engine.
Troubleshooting & FAQ
How do I know if this gasket will fit my engine?
This gasket is for OMC Cobra stern drives (1986–1993) across various engine sizes (2.3L to 5.8L). The best way to confirm fitment is to check your model and year against the compatibility table on this page. Also, verify that your current part number matches one of the cross-references like 915840, 911836, or Sierra 18-2918.
What are the signs of a failed gear housing gasket?
A common sign of failure is water intrusion into the gear lube (milky or creamy-looking oil) or gear lube leaking out of the stern drive unit. You may notice an oil sheen on the water around the drive or a consistent drop in your gear oil level.
Do I need to use sealant with this gasket?
This is a common question. Generally, modern gaskets like this one are designed to be installed dry on clean, flat surfaces. However, some mechanics prefer to apply a very thin layer of a non-hardening sealant. Always consult your specific engine's service manual for the official recommendation.
How often should this gasket be replaced?
This gasket does not have a set replacement interval. It should be replaced anytime the gear housing is separated from the pivot housing for service, or if you detect a leak in that area.
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.
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