





OEM-style lower radiator hose adapter for Volkswagen Mk3 cooling systems. Connects the lower hose to the thermostat housing cover.
$8.99
The 037121619 Lower Radiator Hose Adapter connects the lower radiator hose to the thermostat housing cover on Volkswagen Mk3 cooling systems. It provides the correctly shaped connection needed to maintain coolant circulation between these components. Because the adapter handles constant heat, pressure, and coolant exposure, it can become brittle with age.
A damaged connector may crack, warp, or lose its sealing ability. Consequently, coolant can escape and cause low coolant warnings or overheating. Replacing the adapter at the first sign of deterioration helps restore a dependable cooling-system connection.
The lower radiator hose carries cooled fluid back toward the engine. Therefore, its connection at the thermostat housing must remain secure and leak-free. Even a small crack can become a larger failure once the system reaches operating pressure.
Furthermore, old plastic fittings may break during routine hose service. Installing an OEM-style replacement helps avoid an unexpected coolant loss during daily driving or longer trips. This part is built with the correct diameter and profile for straightforward installation.
Inspect the lower radiator hose connection if you notice any of these warning signs:
Coolant seepage around the thermostat housing cover.
Dried coolant residue near the lower hose connection.
Cracks, swelling, or distortion on the adapter.
A low coolant warning light or frequent coolant top-offs.
Coolant puddles under the front of the vehicle.
A sweet coolant odor after the engine reaches operating temperature.
A connector that breaks or feels brittle during hose service.
OE Part Number: 037 121 619
Function: Connects the lower radiator hose to the thermostat housing cover.
Fitment: Designed for Volkswagen Mk3 cooling-system applications.
Construction: OEM-style material for dependable heat and coolant resistance.
Installation: Correct diameter and shape support a direct replacement fit.
Cross Reference: URO-008056.
Always verify fitment by VIN before ordering. Work only on a completely cool engine because the cooling system can remain pressurized after operation. First, drain the coolant into a suitable container. Then, remove the lower radiator hose and carefully release the old connector.
Inspect the thermostat housing cover before installation. Factory plastic housings can warp or crack during service. In addition, check the hose, clamps, and nearby seals for swelling, corrosion, or wear. Replace damaged parts before refilling the system.
Install the new 037121619 Lower Radiator Hose Adapter with clean sealing surfaces and correctly positioned clamps. Finally, refill with the proper coolant, bleed trapped air, and inspect the connection for leaks after the engine reaches operating temperature.
Always verify fitment by VIN before ordering. This adapter is intended for Volkswagen Mk3 cooling-system configurations.
037 121 619
| Weight | .25 lbs |
|---|---|
| Dimensions | 4 × 3 × 2.5 in |
| Mfg Part # | 037121619 |
| Year | Make | Model | Engine | Notes |
|---|---|---|---|---|
| 1995-2002 | Volkswagen | Cabrio | ||
| 1993-1998 | Volkswagen | Golf | 1.8L | |
| 1993-1998 | Volkswagen | Jetta | 1.8L | |
| 1994 | Volkswagen | Jetta | 2.8L V6 | |
| Volkswagen | Cabrio III | 2.0 | Use vehicle selector to confirm fitment | |
| Volkswagen | Golf III | 2.0 | Use vehicle selector to confirm fitment | |
| Volkswagen | Jetta III | 2.0 | Use vehicle selector to confirm fitment | |
| Volkswagen | Jetta III | TDI | Use vehicle selector to confirm fitment |


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