Spark Plug Wire Set 863656A1 18-8828-1 for MerCruiser 5.0 5.7 6.2 L 350 MAG V8
Spark Plug Wire Set 863656A1 18-8828-1 for MerCruiser 5.0 5.7 6.2 L 350 MAG V8
Product Overview
Spark plug wire set for MerCruiser V8 engines, 5.0 L, 5.7 L and 6.2 L, the full lead set with eight spark plug wires and one coil wire. It replaces 863656A1 and 84-863656A1 and crosses to Sierra 18-8828-1, and the set ships in a 185 mm x 185 mm x 70 mm box.
It fits the 305, 350 and 377 cubic inch small block V8s, which on a MerCruiser means the 5.0 L, the 5.7 L, the 350 MAG and the 6.2 L 377 and 383 engines. Those motors share the same plug positions and the same coil, which is why one set covers the range.
The leads are built for a wet engine bay: Kevlar core, stainless steel wound conductor, and terminals that do not corrode in salt air. On a V8 the leads run close to the manifolds, so heat is the thing that kills them, and a lead that fails hot will cut a cylinder without ever setting a code.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Spark plug wire set, ignition lead set |
| Fits | MerCruiser V8 5.0 L, 5.7 L, 6.2 L |
| Core | Kevlar with stainless steel wound conductor |
| Suppression | Radio and electronics suppression |
| Terminals | Marine grade, corrosion resistant |
| Net Weight | 701 g including packaging |
| Pack Size | 185 mm x 185 mm x 70 mm |
| Quantity | 8 spark plug wires and 1 coil wire |
OEM Cross Reference
| Brand | OEM Part Numbers |
|---|---|
| MerCruiser | 863656A1 |
| MerCruiser, with prefix | 84-863656A1 |
| Sierra | 18-8828-1 |
| CDI | 631-0011 |
| Indmar | 751104, 756004 |
| Mallory | 9-28009 |
Compatible Engines
| MerCruiser Engine | Displacement | Cubic Inches | Note |
|---|---|---|---|
| 5.0 L | 5.0 litre | 305 CID | Small block V8 |
| 5.7 L | 5.7 litre | 350 CID | Small block V8 |
| 350 MAG | 5.7 litre | 350 CID | Magnum small block V8 |
| 6.2 L | 6.2 litre | 377 CID | Small block V8, 377 and 383 |
What's Included
| Component | Detail | Qty |
|---|---|---|
| Spark plug wires | Four pairs, fitted length | 8 |
| Coil wire | From coil to distributor | 1 |
| Distributor cap and rotor | Not included, order separately | 0 |
Misfire or Bad Leads
| What You See | What It Means | What To Do |
|---|---|---|
| Misfire when the engine is hot | Lead breaking down with heat | Renew the set, route away from the manifold |
| Rough idle that clears at speed | One lead or boot arcing | Run in the dark and look for a blue arc |
| Radio clicks with the engine running | Suppression failed in a lead | Renew the set |
| Green corrosion in the boot | Water in the plug well | Renew the lead and dry the well |
| Hard starting when damp | Cracked jacket on a lead | Renew the set before the season |
| Spark at the coil but not the plug | Open circuit in a lead | Meter each lead end to end |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Check the number on the old set, 863656A1 and 84-863656A1 are the same set |
| 2 | Battery off before touching the ignition side |
| 3 | Number the leads before removing them, the longest leads go to the rear cylinders |
| 4 | Clean and dry the plug wells, corrosion there kills new boots |
| 5 | Fit the leads with the boots fully seated on the plugs |
| 6 | Keep the leads off the exhaust manifolds and away from the belts |
| 7 | Start the engine and check for a steady idle on all eight cylinders |
| 8 | Check the coil wire is fully seated at both ends |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | Standard |
| Packaging | Sealed retail packaging |
Before You Buy
- Fits MerCruiser 5.0 L, 5.7 L and 6.2 L V8 engines, including the 350 MAG, 377 and 383
- Replaces 863656A1 and 84-863656A1, crosses to Sierra 18-8828-1 and CDI 631-0011
- The set includes eight spark plug wires and one coil wire
- Kevlar core with a stainless wound conductor and marine grade terminals
- Distributor cap and rotor are not included
- Clean the plug wells and route the leads off the manifolds
- 30-Day Easy Returns
- Ships from our warehouse with tracking
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Before You Buy
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