Flush and refill the cooling system
A biennial cooling-system flush is the single most valuable maintenance job on an Aceca. It removes scale and old inhibitor that quietly line the radiator core and cylinder-head passages, letting the system shed heat properly and preserving the radiator.
Tools
- Ring spanners
- Drain tray at least 10 litres
- Funnel
- Torch
Parts / supplies
- Proprietary cooling-system cleaner
- Manufacturer-specified coolant / corrosion inhibitor
- Distilled or deionised water
- New hose clips if the originals are tired
Procedure
Park the car on level ground and let the engine cool fully. Never open a hot cooling system.
Place a drain tray under the radiator drain tap, open it, and drain the system. Repeat at the block drain if fitted.
Close the drains, refill with clean water plus the cooling cleaner per its label instructions, and run the engine to full temperature.
Let the engine cool, then drain the cleaner. Refill with fresh water only, run to temperature, and drain again to rinse.
Refill with the specified mix of inhibitor / coolant and distilled water in the proportion the coolant maker specifies for this application.
Bleed the system: with the heater on hot, run the engine with the pressure cap off until the coolant level stabilises and no more air rises. Top up and refit the cap.
Run the car up to full temperature, cool it fully, then re-check the level. Top up if needed.
Warnings
- Never open a hot pressurised cooling system. Wait until fully cold.
- Ethylene-glycol coolant is toxic to animals and children. Dispose of drained fluid via a garage or council chemical-waste facility.
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About the author
An independent classic-car enthusiast in North Yorkshire with decades of hands-on experience on British classics — including the AC Aceca — writing the single-model reference he always wished existed. Read the full bio.