OEM-quality 03H121118 Hose Adapter for compatible Volkswagen and Audi cooling systems. Secures the overflow hose and helps maintain coolant pressure.
$12.29
The 03H121118 Hose Adapter is a genuine OEM-quality cooling system component designed to connect and secure the coolant overflow hose. This 03H121118 Hose Adapter supports proper coolant circulation and helps the system maintain the pressure required for stable engine temperatures.
The adapter installs as a direct-fit replacement on applicable Volkswagen and Audi cooling systems. Furthermore, its heat-resistant construction withstands repeated temperature cycles, vibration, and coolant exposure. Therefore, replacing a cracked or worn adapter helps restore a dependable coolant hose connection without modifications.
The cooling system relies on secure hose connections to circulate coolant correctly. A damaged adapter can allow coolant to escape and reduce system pressure. Consequently, low coolant pressure can reduce cooling efficiency and increase the risk of overheating.
Small plastic cooling components often weaken gradually from heat and age. Moreover, a leak may only appear when the engine reaches operating temperature and system pressure rises. Replacing the adapter promptly helps prevent coolant loss, protects nearby components, and supports consistent engine operation.
Inspect the coolant hose adapter if you notice any of these conditions:
Visible coolant residue around the hose connection.
A dropping coolant level in the expansion reservoir.
Cracks, discoloration, or brittle plastic on the adapter.
A sweet coolant odor from the engine bay.
Steam or moisture near the coolant hose connection.
An overheating warning or unstable engine temperature reading.
OE Part Number: 03H 121 118
Function: Connects and secures the coolant overflow hose.
Construction: Durable, heat-resistant plastic for cooling system use.
Fitment: Direct OEM-style replacement on compatible applications.
Protection: Helps prevent coolant leaks and pressure loss.
Installation: No modifications required when correctly matched by VIN.
Always verify fitment by VIN before ordering. First, allow the engine to cool completely before opening the cooling system. Hot coolant can cause serious injury.
Always verify fitment by VIN before ordering. Fitment depends on the engine, cooling system configuration, and original part number.
03H 121 118
| Weight | .15 lbs |
|---|---|
| Dimensions | 3.5 × 2 × 2 in |
| Mfg Part # | 03H121118 |
| Year | Make | Model | Engine | Notes |
|---|---|---|---|---|
| 2021 | Volkswagen | Atlas | 3.6L V6 |
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