Thunderbolt Ignition Sensor 87-892150Q02 for MerCruiser V6 V8 4.3 5.0 5.7 7.4 L
Thunderbolt Ignition Sensor 87-892150Q02 for MerCruiser V6 V8 4.3 5.0 5.7 7.4 L
Product Overview
Thunderbolt ignition sensor kit for MerCruiser V6 and V8 sterndrive engines from 205 HP to 600 HP, replacing 87-892150Q02, 87-861780A2 and 87-91019A3 and crossing to 18-5116-1 and 9-29804. It is supplied as one sensor with an adapter, heat shrink tubing and a screw set.
This is the pickup that reads the distributor trigger wheel on the Thunderbolt IV and V systems fitted to GM based MerCruiser engines from 1981 to 1997. When it fails the engine either has no spark at all or cuts out once hot and restarts after it cools, which is the classic sign: the sensor winding opens when it warms up.
It covers the 4.3 L, 5.0 L, 5.7 L, 7.4 L and 8.2 L V6 and V8 motors across the 205 to 600 model range, in the Thunderbolt I, IV and Gen VI distributors, on MR, Alpha and Bravo drives. Check the distributor cap and rotor first, because a cracked cap produces the same misfire.
Specifications & Attributes
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Ignition sensor kit |
| System | Thunderbolt IV and V electronic ignition |
| Engines | GM V6 and V8, 4.3 L to 8.2 L |
| Years | 1981 to 1997 |
| Components | Sensor, adapter, heat shrink tubing, screw set |
| Country of Origin | Taiwan |
OEM Cross Reference
| Brand | OEM Part Numbers |
|---|---|
| MerCruiser | 87-892150Q02, 87-892150A02, 892150A02 |
| MerCruiser | 87-861780A2, 87-861780Q4, 87-861780A4 |
| MerCruiser | 87-91019A2, 87-91019A3, 87-91019A6 |
| Aftermarket | 18-5116-1 |
| Mallory | 9-29804 |
Compatible Engines
| Engine | Displacement | Model Range |
|---|---|---|
| V6 | 4.3 L | 205, 240 HP |
| V8 | 5.0 L | 260 HP |
| V8 | 5.7 L | 260, 305, 320, 350 HP |
| V8 | 7.4 L | 425, 450, 454, 465 HP |
| V8 | 8.2 L | 500, 502, 525, 575, 600 HP |
| Distributors | All | Thunderbolt I, IV, Gen VI |
What's Included
| Component | Qty |
|---|---|
| Ignition sensor | 1 |
| Adapter | 1 |
| Heat shrink tubing | 2 |
| Screw set | 1 |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | Standard |
| Packaging | Sealed retail packaging |
Before You Buy
- Check the distributor is a Thunderbolt IV or V, the Thunderbolt III and the later Delco EST use a different sensor
- Check the cap, rotor and plug leads first, they cause the same no spark or hot cut out
- Check the trigger wheel for rust and the air gap while the cap is off
- Route the new wiring away from the exhaust manifolds and use the heat shrink supplied
- Check the distributor gear and timing after fitting, and set the base timing as the manual specifies
- Run the engine to full temperature and shut it down twice to confirm the hot restart fault is gone
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