Type 25 Water Hose - Expansion Tank To Water Pump - 1986-92

This replacement rubber coolant hose connects the expansion (header) tank to the water pump via the water pump–to–thermostat metal pipe (025121081G) on 1900cc and 2100cc petrol Waterboxer engines fitted to VW Type 25 buses from 1985 onwards. It is the correct hose for non-Syncro (2WD) models only.

Important: Not for Syncro models. For Syncro, use part number 025121108H.

On later Waterboxer cooling systems, this hose forms a critical link in the pressure and return circuit, allowing coolant from the expansion tank to feed back toward the water pump through the metal pipe. A sound hose here is essential for maintaining correct coolant levels, stable system pressure, and reliable circulation. Age-hardened or swollen originals are a common source of leaks and air ingress.

Manufactured from high-quality NBR fabric-reinforced rubber, this hose is moulded to the exact OE shape and specification, ensuring perfect fitment, correct routing, and long service life under heat and pressure.

What this hose does and how it works

As coolant expands and contracts with temperature, the expansion tank manages system volume and pressure. This hose carries coolant from the tank into the pump feed circuit (via the metal pipe), ensuring the pump always has a steady supply. Proper sealing here prevents air being drawn into the system and supports consistent operating temperatures.

Fitment

• Vehicle: Type 25 / T3 (2WD / Non-Syncro only)

• From: 1985 onwards

• Engines: 1900cc & 2100cc petrol Waterboxer

• Application: Expansion tank to water pump (via metal pipe 025121081G)

Engine code compatibility

• DF: 1.9 (08/85 – 07/92)

• EY: 1.9 (08/85 – 07/89)

• DJ: 2.1 (08/85 – 07/92)

• MV: 2.1 (08/85 – 07/92)

Quality

• NBR fabric-reinforced rubber

• OE-correct moulded profile

• Resistant to heat, pressure, and coolant exposure

Fitting requirements (sold separately)

• 1 × 27mm hose clip: N0164031

• 1 × 32mm hose clip: N0164041

Fitting notes

• Inspect the metal pipe (025121081G) for corrosion and replace if necessary

• Ensure hose ends seat fully before tightening clips

• Refill with the correct coolant and bleed the system thoroughly after installation

A correctly formed, high-quality replacement that helps keep your Waterboxer cooling system sealed, properly pressurised, and reliable.