Ignition Sensor Kit – Fits MerCruiser V6 & V8 (Replaces 87-892150Q02, 87-91019A3)
Ignition Sensor Kit – Fits MerCruiser V6 & V8 (Replaces 87-892150Q02, 87-91019A3) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Ignition Sensor Kit – Fits MerCruiser V6 & V8 (Replaces 87-8921...
Product Details
This Ignition Sensor Kit – Fits MerCruiser Thunderbolt IV & V Ignition (Replaces 87-892150Q02, 87-91019A3) is designed for MerCruiser V6 and V8 marine engines (4.3L, 5.0L, 5.7L, 7.4L, 8.2L) equipped with Thunderbolt IV and V electronic ignition systems from 1981–1997. It serves as a direct replacement, ensuring reliable ignition performance for a wide range of popular marine engines.
It serves as a direct replacement for multiple Mercury/MerCruiser, Sierra, Mallory, and CDI part numbers, ensuring a precise fit and reliable performance.
- Designed for simple, direct replacement installation.
- Features a robust glass-filled polyester housing for durability in marine environments.
- Includes lead wires and all necessary mounting hardware for a complete installation.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury/MerCruiser | 87-892150Q02 |
| Mercury/MerCruiser | 87-892150A02 |
| Mercury/MerCruiser | 87-91019A3 |
| Mercury/MerCruiser | 87-91019A2 |
| Mercury/MerCruiser | 861780A2 |
| Mercury/MerCruiser | 861780Q4 |
| Mercury/MerCruiser | 87-892150K02 |
| Sierra | 18-5116-1 |
| Mallory | 9-29804 |
| CDI | E11-0005 |
| GLM | 73110 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This sensor fits a wide range of MerCruiser engines with Thunderbolt IV and V ignition systems. Please verify your specific model and year against the list.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | 4.3L (2 BBL.) | 175-185 | 4-Stroke | 1985–1992 | 87-91019A2 | GM 262 V-6 |
| MerCruiser | 4.3LX (4 BBL.) | 205 | 4-Stroke | 1987–1992 | 87-91019A2 | GM 262 V-6 |
| MerCruiser | 5.0L (4 BBL.) | 200-230 | 4-Stroke | 1981–1995 | 87-91019A2 | GM 305 V-8 |
| MerCruiser | 5.7L | 260-350 | 4-Stroke | 1986–1995 | 87-91019A2 | GM 350 V-8 |
| MerCruiser | 7.4L | 320-425 | 4-Stroke | 1981–1996 | 87-91019A2 | GM 454 V-8 |
| MerCruiser | 8.2L | 425-500 | 4-Stroke | 1990–1996 | 87-91019A2 | GM 502 V-8 |
Technical Specs
- Product Type
- Ignition Sensor Kit
- Installation
- Direct replacement
- Housing Material
- Glass-filled polyester
- Connection
- Lead wires with connectors
- Maximum Supply Voltage
- 12 Volts
- Mounting Type
- Flange Mount
- Output Type
- Electrical signal
- Dimensions
- 160 × 76 × 56 mm (6.3 × 2.99 × 2.2 inches)
- Weight
- 0.132 kg (4.66 ounces)
- Other Technical Attributes
- Designed for marine applications with corrosion resistance
What’s in the Box
- 1 x Ignition Sensor
- 1 x Set of Lead Wires with Connectors
- 1 x Hardware Kit (mounting screws and fasteners)
Installation Notes
- Disconnect the negative battery terminal to prevent electrical shorts.
- Locate and carefully remove the distributor cap and rotor to access the ignition sensor.
- Note the routing of the old sensor's wires, then disconnect them.
- Unscrew and remove the old ignition sensor from the distributor housing.
- Mount the new sensor in place, ensuring it is seated correctly, and fasten the screws.
- Connect the new sensor's lead wires, following the path of the original wires.
- Reinstall the distributor rotor and cap.
- Reconnect the negative battery terminal and test the engine to confirm proper operation.
Troubleshooting & FAQ
How do I know if my ignition sensor is failing?
Common signs of a faulty ignition sensor include engine misfires, erratic tachometer behavior, stalling, difficulty starting, or a complete loss of spark. Running a diagnostic check can often confirm a sensor-related fault code.
Is this compatible with both Thunderbolt IV and V systems?
Yes, this sensor is designed to be fully compatible with both MerCruiser Thunderbolt IV (TB4) and Thunderbolt V (TB5) ignition systems on the specified V6 and V8 engines from 1981–1997.
What is the difference between part 87-91019A3 and 87-892150Q02?
These part numbers, along with others like 87-91019A2, are often used interchangeably as they represent the same component or have been superseded. This aftermarket kit is a direct replacement for all listed equivalent part numbers.
Will this fix a "no spark" issue in my engine?
A failed ignition sensor is a common cause of a "no spark" condition. While replacing it can resolve the issue, other components like the ignition coil, distributor cap, rotor, or wiring could also be at fault. Proper diagnosis is recommended.
What is the recommended replacement interval for an ignition sensor?
There is no fixed replacement interval. Ignition sensors are typically replaced only when they fail. However, if you are performing a major ignition system overhaul, it is good preventative maintenance to replace it.
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.
Payment & Security
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