Radiator Top / Bottom Hoses
Fits:
Porsche 944 1981-85
Engine type: 4401 / 4402 / 4403 / 4404
M 41D 1286 >>
M 41D 5165 >>
M 43D 3440 >>
M 43D 5518 >>
Diagram ref no 9A
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
94410623902
The product you are viewing cross references to these numbers
- Porsche 944 2.5L 8V 1982-87
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12 Month Warranty
Worldwide Delivery
This replacement coolant hose connects the upper radiator outlet to the cylinder head on early Porsche 944 models (1981-85). This hose conforms to original Porsche specifications in diameter, length, routing, and material grade. Constructed from high-temperature-resistant rubber with the correct wall thickness, it restores proper coolant flow, prevents leaks, and maintains the reliability of the vehicle's cooling system.
Fits:
Porsche 944 1981 - 1985
Engine type: 4401 / 4402 / 4403 / 4404
M 41D 1286 >>
M 41D 5165 >>
M 43D 3440 >>
M 43D 5518 >>
Diagram ref no 9A.
• Position on Vehicle: Engine bay – upper radiator hose connecting the top of the radiator to the cylinder head.
The upper radiator hose is a critical link in the engine’s cooling circuit: if it fails, you risk coolant leaks, overheating, engine damage, loss of heater performance and unexpected roadside breakdowns. Symptoms of a failing hose include bulging, cracking, coolant smell, visible coolant loss or temperature rise. Replacing the hose ensures proper coolant delivery, secure clamping, correct routing and long-term reliability.
When and why to replace:
• Visible cracks, bulging or soft spots on the existing hose.
• Hose has become hard, inflexible or distorted and may collapse under engine vacuum/pressure.
• Leaks or coolant loss are detected at the top radiator connection.
• During cooling system service: radiator removal, cylinder head service or hose age exceeds recommended lifespan (especially on classic vehicles).
• When the vehicle is undergoing restoration and you require correct-spec parts for peace of mind and authenticity.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
94410623902
The product you are viewing cross references to these numbers
- Porsche 944 2.5L 8V 1982-87
Shop Securely
12 Month Warranty
Worldwide Delivery
Fits:
Porsche 944 S 2.7L 1989 M44.11/12 engines
Porsche 944 S2 3.0L 1989-91 M44.41 engine
Click 'Zoom in' for large parts diagram.
Diagram ref no 37
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
94410610302
The product you are viewing cross references to these numbers
- Porsche 944 2.7L 8V 1988-89
- Porsche 944S2 3.0L 16V 1989-91
Shop Securely
12 Month Warranty
Worldwide Delivery
Radiator Top & Bottom Hoses – Reliable Cooling for Porsche Performance
Radiator top and bottom hoses are vital components of your Porsche’s cooling system, responsible for transporting coolant between the radiator and the engine. The top hose carries hot coolant from the engine to the radiator for cooling, while the bottom hose returns the cooled fluid back to the engine, maintaining optimal operating temperatures for performance, efficiency, and reliability.
At Design911, we offer a full range of genuine and manufacturer-quality radiator top and bottom hoses for Porsche models including 911, Boxster, Cayman, Cayenne, Macan, and Panamera. Each hose is precision-engineered for perfect fitment, high pressure tolerance, and exceptional heat resistance — ensuring reliable cooling under the most demanding driving conditions.
What Do Radiator Top and Bottom Hoses Do?
Coolant hoses are the lifelines of your Porsche’s cooling
system, and the radiator hoses perform the following key functions:
- Carry
coolant between the radiator and the engine.
- Regulate
engine temperature for consistent performance.
- Maintain
coolant pressure throughout the cooling circuit.
- Prevent overheating by ensuring efficient heat transfer.
Both the top and bottom hoses are designed to withstand high heat, vibration, and coolant pressure, providing dependable performance in every driving scenario.
Why Do Radiator Hoses Fail?
Over time, radiator hoses deteriorate due to heat, pressure,
and exposure to coolant. Common causes of hose failure include:
- Rubber
cracking or hardening from continuous heat cycles.
- Swelling
or soft spots due to coolant chemical breakdown.
- Leaks
at hose ends or clamps from pressure loss.
- Abrasion
damage caused by engine vibration or contact.
- Age-related material fatigue, especially in older vehicles.
Symptoms of hose failure include coolant leaks, visible cracks or bulges, fluctuating engine temperature, or a noticeable coolant smell in the engine bay.
Why Replace Faulty Radiator Hoses?
A leaking or weakened radiator hose can lead to overheating, coolant loss, and potential engine damage. Replacing these hoses as part of routine maintenance ensures consistent cooling performance and reliability.
Benefits of replacement include:
- Restored coolant flow and temperature stability.
- Prevention of leaks and overheating.
- Improved cooling system pressure and performance.
- Manufacturer-quality materials for long-term durability.
All radiator hoses in this range are made using reinforced, high-grade rubber and polymer compounds, designed to meet or exceed factory specifications for heat resistance, flexibility, and longevity.
