Knock Sensor for GM V8 305, 350 & 377 CID Marine Engines – MerCruiser, OMC Cobra & Volvo Penta
Knock Sensor for GM V8 305, 350 & 377 CID Marine Engines – MerCruiser, OMC Cobra & Volvo Penta is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
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Knock Sensor for GM V8 305, 350 & 377 CID Marine Engines – MerC...
Knock Sensor for GM V8 305, 350 & 377 CID Marine Engines – MerCruiser, OMC Cobra & Volvo Penta is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket Knock Sensor is intended for GM small-block V8 marine engines with 305, 350, and 377 cubic-inch displacements. The company fitment specifically covers applications used with MerCruiser stern-drive and inboard/outdrive systems, OMC Cobra stern-drive and outdrive systems, and Volvo Penta stern-drive and outdrive systems.
The sensor is used to detect engine vibration associated with knock or detonation and provide the engine management system with a corresponding signal. Confirm the engine application, connector, mounting arrangement, and original part number before ordering.
OEM & Aftermarket Reference Numbers
The following manufacturer and aftermarket numbers are listed as reference numbers for this sensor. Reference-number listings do not replace the need to verify the complete engine application.
| Brand or source | Reference number |
|---|---|
| Mercury MerCruiser | 806612T |
| Volvo Penta | 22024631 |
| Volvo Penta | 3850357 |
| Volvo Penta | 3861977 |
| OMC | 3850357 |
| Pleasurecraft | R020027 |
| Sierra Marine | 18-7677 |
| Mallory Marine | 9-33503 |
Engine Compatibility
Company-listed engine fitment is shown below. No specific model years, serial-number ranges, shaft dimensions, or individual engine model codes are supplied for this product, so those details should be checked against the engine identification label and the original sensor.
| Engine platform | Displacement | Application notes |
|---|---|---|
| GM small-block V8 marine engines | 305 CID | Verify the original sensor and connector before installation. |
| GM small-block V8 marine engines | 350 CID | Verify the original sensor and connector before installation. |
| GM small-block V8 marine engines | 377 CID | Verify the original sensor and connector before installation. |
Application Coverage
- MerCruiser stern-drive and outdrive applications
- OMC Cobra stern-drive and outdrive applications
- Volvo Penta stern-drive and outdrive applications
- GM V8 marine engines with 305, 350, or 377 CID displacement
Technical Specifications
- Part type
- Knock sensor
- Engine platform
- GM small-block V8 marine engines
- Listed displacements
- 305, 350, and 377 CID
- Application
- MerCruiser, OMC Cobra, and Volvo Penta stern-drive/outdrive systems
- Product type
- Aftermarket replacement sensor
What's in the Box
- 1 × Knock sensor
Installation Notes
- Disconnect the battery and allow the engine to cool before beginning work.
- Locate the knock sensor using the engine service manual for your specific GM marine engine.
- Compare the replacement sensor with the original part, including the connector, threaded mounting area, and overall configuration.
- Disconnect the electrical connector from the original sensor.
- Remove the original sensor with the appropriate tool.
- Inspect the mounting area and threads for corrosion, damage, or debris.
- Install the replacement sensor according to the engine manufacturer's service instructions. Use only the specified tightening procedure and torque for your engine application.
- Reconnect the electrical connector and confirm that it is fully seated.
- Reconnect the battery and check for warning lights or diagnostic fault codes after starting the engine.
Important: Do not use a generic torque value for every application. Knock-sensor installation requirements can vary by engine design; consult the applicable service manual.
Troubleshooting & FAQ
Which engines does this knock sensor fit?
The company-listed fitment is GM small-block V8 marine engines with 305, 350, and 377 cubic-inch displacements. The listed marine applications include MerCruiser, OMC Cobra, and Volvo Penta stern-drive or outdrive systems.
Is this an OEM sensor?
No. This listing is for an aftermarket replacement sensor. The reference numbers are provided to help compare the replacement with the original application.
What reference numbers are associated with this sensor?
Company-listed references include MerCruiser 806612T, Volvo Penta 22024631, 3850357, and 3861977, OMC 3850357, Pleasurecraft R020027, Sierra Marine 18-7677, and Mallory Marine 9-33503.
How can I confirm compatibility before ordering?
Match the engine displacement, marine brand and drive system, original sensor, electrical connector, and reference number. Because specific year and serial-number coverage is not provided for this listing, use the engine service manual or the original part for final verification.
What symptoms may be associated with a faulty knock sensor?
Possible symptoms can include a warning light, diagnostic fault codes, reduced performance, or abnormal engine-control behavior. These symptoms can also be caused by wiring, connector, fuel, ignition, or other engine-management problems, so test the complete system before replacing the sensor.
Can I install the sensor without checking the service manual?
No. The mounting location and tightening procedure depend on the specific engine. Follow the applicable service manual and avoid using an unverified universal torque specification.
Safety & Important Information
- Verify the engine displacement, application, connector, and original part number before ordering.
- Specific model-year and serial-number ranges are not supplied for this listing.
- This is an aftermarket replacement, not an OEM component.
- Disconnect the battery and work only on a cool engine.
- Professional installation is recommended when the correct mounting procedure or diagnostic process is uncertain.
About Sea Sierra
- Marine replacement parts selected for common stern-drive, outdrive, and inboard applications.
- Application-focused listings with manufacturer and aftermarket reference numbers for comparison.
- Support for customers verifying marine engine fitment before ordering.
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