Cooling system — flushing (Opel Ascona C)

1. Over time, the system may lose its efficiency due to clogging of the radiator with rust, scale, sediment, etc. This is one of the reasons why the engine of older cars overheats more often than that of new ones. To restore the efficiency of the system, it must be flushed. Drain the coolant (see previous section) and remove the thermostat (see section 8). Temporarily install the thermostat housing in place and connect the hose. Disconnect the upper hose from the radiator and cover the engine with a plastic sheet to prevent it from getting wet while flushing the system.

2. Using a garden hose, flush the radiator until clear water comes out. If the radiator is heavily contaminated, disconnect its lower hose and direct the flow to the lower part of the radiator (backwash). Repeat the above procedure on the cylinder block. If you feel that the radiator is not clean enough after backwashing, it should be removed (see section 7) and rinse with shaking. After backflushing, flush the radiator again in the normal direction and only then install the thermostat and connect the system hoses.

3. In extreme cases, it may be necessary to use special descaling compounds (Holts Radflush or Holts Speedflush). When working with them, strictly follow the manufacturer's instructions.

4. Since the coolant is never completely drained, the system should be flushed every time the coolant is changed.

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