Universal 1/8" NPT Temperature Sender for Oil/Water Monitoring (0–150°C / 0–300°F)
Universal 1/8" NPT Temperature Sender for Oil/Water Monitoring (0–150°C / 0–300°F) is backordered and will ship as soon as it is back in stock.
Worry-free returns
Worry-free returns
Shop with confidence. If you’re not completely satisfied, eligible items may be returned within the return window, provided they are unused and in original packaging.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
International delivery times may vary due to customs processing.
Tracking information will be provided once your order ships.
Universal 1/8" NPT Temperature Sender for Oil/Water Monitoring...
Universal 1/8" NPT Temperature Sender for Oil/Water Monitoring (0–150°C / 0–300°F) is backordered and will ship as soon as it is back in stock.
Product Details
This Universal 1/8" NPT Temperature Sender for Oil/Water Monitoring (0–150°C / 0–300°F) is a direct-fit replacement for Mercury and Mariner outboard and inboard engines that require OEM part 12415. Engineered for accuracy, it monitors engine oil or water temperature to ensure your vessel operates within safe limits.
It serves as a direct interchange for Mercury 12415 and Sierra 18-5896.
- Features a standard 1/8" NPT single-wire threaded connection for straightforward installation.
- Monitors a wide temperature range of 0–150°C (0–300°F).
- Constructed from high-quality brass for durability and corrosion resistance in marine environments.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 12415 |
| Sierra | 18-5896 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This sender has a universal application for many Mercury and Mariner models. Please verify your original part number is 12415.
| Brand | Model | Rated HP | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Mercury | Various Models | Multiple | 2- & 4-Stroke | 12415 | Universal application |
Technical Specs
- Product Type
- Temperature Sender / Sensor
- Installation
- Direct Thread
- Connection
- Single Wire
- Thread Size
- 1/8" NPT (18-27 NPT threads)
- Housing Material
- Brass
- Operating Temperature
- 0–150°C (0–300°F)
- Application
- Oil/water temperature monitoring
- Condition
- Brand new
What’s in the Box
- 1 × Temperature Sender Unit (12415)
Installation Notes
- Ensure the engine is cool and disconnect the battery's negative terminal for safety.
- Locate the existing temperature sender on the engine block or cylinder head.
- Carefully disconnect the single wire connector from the old sender.
- Using an appropriately sized wrench, unscrew and remove the old sender. Have a rag ready to catch any minor fluid drips.
- Apply a suitable thread sealant to the threads of the new sender to prevent leaks. Do not overtighten.
- Install the new sender by screwing it into place and tightening it to the manufacturer's recommended torque specification.
- Reconnect the single wire connector securely.
- Reconnect the battery's negative terminal.
- Start the engine and check the temperature gauge for correct operation. Inspect for any leaks around the new sender.
Troubleshooting & FAQ
How do I confirm this sender fits my specific engine model?
The surest way is to match the part number. This sender replaces OEM part 12415. While it has a universal design for many Mercury/Mariner engines, always verify your old part's number and thread size (1/8" NPT) before ordering.
What are common signs of a failing temperature sender?
A faulty sender can cause your temperature gauge to read erratically (jumping), stay stuck on cold, max out on hot, or not work at all. This can prevent you from knowing if your engine is overheating.
What is the resistance curve for this sender?
While specific electrical specifications like resistance values are not provided, this unit is designed to work with standard marine gauges expecting input from a 12415-type sender within the 0–300°F (0–150°C) range.
Can I use this for a different application besides oil or water temperature?
This sender is specifically designed and calibrated for monitoring oil and water temperature in marine engines. Using it for other purposes is not recommended as its accuracy and durability are not guaranteed for other fluids or environments.
Is this an OEM part?
This is an aftermarket replacement part, not an original equipment manufacturer (OEM) component. It is engineered to meet or exceed OEM specifications using comparable materials and is produced in an ISO 9002 certified facility with rigorous quality control.
What is the shipping speed and cost?
We ship worldwide quickly, with typical transit times of 5–15 days. Standard shipping is free for most orders, and expedited options are available at checkout where applicable.
What is the warranty and return policy?
This product 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 unused items in their original condition. See our policy page or contact us 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.
Payment & Security
Payment methods
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