The Honda 12251-ZG8-003 Cylinder Head Gasket is a genuine OEM replacement designed for GX640 horizontal shaft engines, H4013 lawn tractors, H4514 lawn tractors, H4518 lawn tractors, and H5518 multi-purpose tractors. As a direct OEM component, this gasket is manufactured to Honda's exact specifications, ensuring a correct seal between the cylinder head and engine block. Confirm your machine's serial number against the fitment table before ordering, as Honda supersedes parts at serial breaks and fitment can vary within a model series.
Key Features
- Cylinder Head Sealing — engineered to Honda's exact head-surface specifications, this gasket maintains the combustion seal that proper compression and cylinder head clamping depend on
- Genuine OEM Part — sourced directly from Honda, part number 12251-ZG8-003 carries the same specification.
- Broad Fitment — fits GX640 horizontal shaft engines and Honda H4013, H4514, H4518 lawn tractors and H5518 multi-purpose tractors; verify your serial number against the fitment table to confirm the correct application
- Restored Compression — a failed or leaking cylinder head gasket causes loss of compression, overheating, and oil or coolant intrusion; replacing it with this OEM gasket restores the sealing integrity the engine requires to run correctly
The cylinder head gasket sits between the cylinder head and the engine block, forming a gas-tight seal that contains combustion pressure and keeps engine oil from migrating into the combustion chamber. It is one of the most structurally critical seals in a four-stroke engine: when it fails, combustion gases can escape, compression drops sharply, and the engine will overheat or run erratically. Replacing a blown or degraded gasket with a correctly specified OEM part like the Honda 12251-ZG8-003 Cylinder Head Gasket is essential to restoring full power output and protecting the engine from further damage.
Part Details
| Part Number | 12251-ZG8-003 |
|---|---|
| Brand | Honda |
| Part Type | Genuine OEM |
| Description | Cylinder Head Gasket |
Compatibility & Fitment
| Name | Models | Serial Range |
|---|---|---|
| Horizontal Shaft Engine | GX640 | All |
| Lawn Tractor | H4013, H4514, 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.
