The Honda 30500-ZG8-003 Ignition Coil Assembly is a genuine OEM component designed for GX640 horizontal shaft engines, H4518 lawn tractors, and H5518 multi-purpose tractors. As a direct Honda OEM replacement, this ignition coil assembly is manufactured to the same specifications as the original unit it replaces, ensuring a correct, drop-in fit with no guesswork. Honda supersedes ignition components at serial-number breaks, so confirm your machine's serial number against the fitment table before ordering to make sure part number 30500-ZG8-003 is the right assembly for your unit.
Key Features
- Genuine OEM Ignition Output — Honda-sourced construction delivers the correct spark voltage and timing curve that GX640 engines and the H4518 and H5518 tractors were engineered around, keeping combustion consistent across the full operating range.
- Direct OEM Replacement — replaces the original ignition coil assembly exactly, with Honda's correct mounting geometry and air-gap specification so the coil installs straight from the box.
- Broad Fitment Across GX640 and Tractor Applications — covers GX640 horizontal shaft engines as well as H4518 and H5518 tractors; check your serial number against the fitment table to confirm applicability for your specific unit.
- Serial-Number Verification Recommended — Honda updates ignition components at production breaks, so matching your machine's serial number to the fitment table is the most reliable way to confirm this is the correct assembly.
- Restored Starting Reliability — a failed or weakened ignition coil produces a weak or absent spark, leading to hard starting, misfires, and stalling under load; replacing it with this genuine assembly restores crisp ignition and smooth engine operation.
The ignition coil assembly generates the high-voltage electrical pulse that fires the spark plug at precisely the right moment in the engine's combustion cycle. It does this by stepping up low-voltage current from the flywheel's passing magnets into the thousands of volts needed to jump the spark plug gap and ignite the air-fuel mixture. When the coil weakens or fails, the engine may crank without starting, misfire at speed, or cut out under load — symptoms that worsen as the coil heats up during operation. Replacing a degraded coil assembly with a genuine Honda unit restores full spark energy and returns the engine to dependable, consistent performance.
Part Details
| Part Number | 30500-ZG8-003 |
|---|---|
| Brand | Honda |
| Part Type | Genuine OEM |
| Description | Ignition Coil Assembly |
Compatibility & Fitment
| Name | Models | Serial Range |
|---|---|---|
| Horizontal Shaft Engine | GX640 | All |
| Lawn Tractor | H4518 | All |
| Multi-Purpose Tractor | H5518 | All |
Verify Before You Order
Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.
Why Buy From DHS Equipment
Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.
Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.
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