Radiator Top / Bottom Hoses

Fits:
Porsche 928 1978-1984
Click 'Zoom in' for large parts diagram.
Diagram ref no 19
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
92810623806
The product you are viewing cross references to these numbers
- Porsche 928 4.5L 1978-82
- Porsche 928S 4.7L 1981-83
- Porsche 928S2 4.7L 1984-86
Replacement hose for the upper radiator hose used in Porsche 928 models. It connects the radiator to the temperature regulator (thermostat/expander) housing, which is part of the engine cooling system. It ensures proper coolant flow between the radiator and engine, supporting precise temperature control.
Fits:
Porsche 928 1978 - 1984
Diagram ref no 19
• Location: Upper radiator hose — radiator to thermostat / water-regulator housing
• Use Case: Replacement during maintenance, cooling system overhaul, or when hose shows leak, age or wear
Manufactured to the original dimensions, inside diameter, and hose shape, this replacement hose ensures a proper fit and reliable seal without the need for modification. Made of high-quality, heat-resistant rubber, it withstands engine temperatures, pressure cycles, and coolant exposure, ensuring reliable, long-lasting performance.
This hose is especially useful when the original hose becomes brittle, cracked, swollen, or leaking, which are common problems in older cooling systems. Installing a new hose helps prevent coolant leaks, overheating, and potential engine damage.
Hoses degrade over time due to heat, coolant chemicals, age, and repeated expansion / contraction. A failing radiator hose can lead to:
• Coolant leaks under bonnet or beneath car
• Engine overheating or overheating under heavy load
• Loss of coolant pressure or coolant circulation
• Risk of engine damage due to poor cooling
Replacing it with a correctly spec’d hose helps maintain coolant circulation, prevents leaks, and safeguards the engine’s cooling system reliability.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
92810623806
The product you are viewing cross references to these numbers
- Porsche 928 4.5L 1978-82
- Porsche 928S 4.7L 1981-83
- Porsche 928S2 4.7L 1984-86
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.