Oil Pressure Sensor – Fits MerCruiser V6 & V8 Engines (Replaces 815425T, 34623)
Oil Pressure Sensor – Fits MerCruiser V6 & V8 Engines (Replaces 815425T, 34623) 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).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Oil Pressure Sensor – Fits MerCruiser V6 & V8 Engines (Replaces...
Product Details
This Oil Pressure Sensor – Fits MerCruiser V6 & V8 Engines accurately monitors engine oil pressure for a wide range of MerCruiser and Volvo Penta inboard and stern drive engines from 1975 and later. Featuring a standard 1/8" NPT thread and an 80 PSI operating range, it provides reliable readings to compatible electric oil pressure gauges, ensuring your engine's health is always in check.
This sensor is a direct cross-reference for multiple OEM and aftermarket part numbers, including MerCruiser 815425T, Volvo Penta 172127, OMC 3853800, and Sierra 18-5899.
- Installs directly by threading into the engine block.
- Designed for use with 80 PSI electric oil pressure gauges.
- Produced in an ISO 9002 certified factory for quality assurance.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| MerCruiser/Mercury | 34623, 815425, 815425T, 8M0068784, 90806, 90806A1 |
| Volvo Penta | 172127 |
| OMC | 3853800, 3857532 |
| PCM | 982650 |
| Chrysler | 90512 |
| Sierra | 18-5899 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Fits various MerCruiser V6 and V8 stern drive and inboard gas engines, including 3.0L, 4.3L, 5.0L, 5.7L, 7.4L, and 8.2L models.
Compatible with Volvo Penta and OMC 4-cylinder, V6, and V8 engines (3.0L, 4.3L, 5.0L, 5.7L, 7.4L, 8.2L).
| Brand | Model | CID | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|---|
| MerCruiser/Mercury | Stern Drive 3.0L | 181 | 4-Stroke | 815425T, 34623 | V4 Inline |
| MerCruiser/Mercury | Stern Drive 4.3L | 262 | 4-Stroke | 815425T, 34623 | V6 |
| MerCruiser/Mercury | Stern Drive 5.0L, 5.7L, 7.4L, 8.2L | 305-502 | 4-Stroke | 815425T, 34623 | V8 |
| MerCruiser/Mercury | Crate Engines 5.7L | 350 | 4-Stroke | 815425T, 34623 | V8 Models |
| MerCruiser/Mercury | Inboard Gas Engines 5.7L, 6.2L, 7.4L, 8.2L | 350-502 | 4-Stroke | 815425T, 34623 | V8 Models |
| Volvo Penta | 4L, V6, V8 Engines | 4-Stroke | 172127 | 3.0L, 4.3L, 5.0L, 5.7L, 7.4L, 8.2L | |
| OMC | 4L, V6, V8 Engines | 4-Stroke | 3853800, 3857532 | 3.0L, 4.3L, 5.0L, 5.7L, 7.4L, 8.2L |
Technical Specs
- Product Type
- Oil Pressure Sensor/Sender
- Installation
- Direct thread into engine block
- Thread Size
- 1/8" NPT (3.2mm-27)
- Pressure Range
- 80 PSI
- Terminal Type
- 10-32 stud
- Housing Material
- Brass with zinc plating
- Housing Color
- Silver/Gold
- Working Pressure
- 80 PSI
- Compatibility
- For use with 80 PSI electric oil pressure gauges
- Manufacturing
- Produced in ISO9002 certified factory
What’s in the Box
- 1 x Oil Pressure Sensor (Part #34623)
Installation Notes
- Disconnect the battery terminals to ensure safety.
- Locate the existing oil pressure sensor on the engine block. Place a rag underneath to catch any residual oil drips.
- Unplug the electrical connector from the old sensor.
- Using an appropriate wrench, carefully unscrew and remove the old sensor.
- Clean the threads on the engine block to ensure a clean sealing surface.
- Apply a suitable thread sealant or Teflon tape to the threads of the new sensor.
- Screw the new sensor in by hand, then tighten gently with a wrench until snug. Do not overtighten.
- Reconnect the electrical connector securely.
- Reconnect the battery terminals.
- Start the engine and check for any leaks around the sensor and verify the gauge is providing a reading.
Troubleshooting & FAQ
How do I know if my oil pressure sensor is failing?
Common signs of a faulty oil pressure sensor include an oil pressure gauge that reads zero, is maxed out, or provides erratic readings. The engine's warning light may also illuminate.
Will this work with a 60 PSI gauge?
No, this sensor is calibrated for an 80 PSI pressure range and must be paired with a compatible 80 PSI electric gauge for accurate readings. Using it with a gauge of a different range will result in incorrect pressure displays.
Is thread sealant required for installation?
Yes, applying a small amount of thread sealant or tape appropriate for marine applications is recommended on the 1/8" NPT threads. This helps create a leak-proof seal. Avoid over-application and do not overtighten the sensor.
What if my engine model isn't on the compatibility list?
This sensor is confirmed to fit the listed models. If your model is not listed, do not purchase. Please verify your original part number and confirm the thread size (1/8" NPT) and pressure range (80 PSI) match before ordering.
What is the difference between an OEM and an aftermarket part?
This listing is an aftermarket replacement, not an original equipment manufacturer (OEM) part. It has been built to meet or exceed OEM-level specifications using comparable materials and is manufactured in an ISO 9002 certified facility with batch inspections for quality and consistency.
How much is shipping and how fast will I get my order?
We ship worldwide quickly—typical transit is 5–15 days for most regions. Standard shipping is free. Expedited shipping options, if available for your location, will be presented at checkout.
What is your warranty and return policy?
This part is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard window for items that are unused and in their original condition. See our policy page or reach out for instructions.
Safety & Important Info
- Verify images and specifications against your original part before purchasing. If anything differs—even if your model appears on a compatibility list—do not purchase.
- This product is an aftermarket replacement part, not an OEM component.
- Professional installation is strongly recommended for safety and to ensure optimal performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and rigorously tested for real-world conditions.
- Fast Global Fulfillment — We offer free standard delivery to most regions, with an average transit time of 5–15 days.
- Manufacturer-Direct Value — Our direct sourcing model allows us to provide fair pricing without compromising on materials or quality control.
Payment & Security
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