How to Quick Flush Your Cars Cooling System, by ChrisFix on YouTube. 6 min 50 s.
- Video length
- 6 min 50 s
- Time to do it
- 1 hour
- Difficulty
- Medium
- Steps
- 9
What you need
Steps
Park on level ground and let the engine cool completely, at least an hour. Never open the radiator cap while the engine is hot, because scalding coolant can spray out.
Slide a drain pan under the radiator drain valve, open it with a wrench or by hand and let the old coolant run out. Close the valve when the flow stops.
Fill the radiator with distilled water, then add the coolant flush chemical following the dose on the bottle.
Start the engine and turn the heater to full hot. Run it for the time stated on the flush bottle, usually 10 to 15 minutes, until the radiator fan cycles.
Switch the engine off and let it cool, then drain the flush water and chemical into the pan.
Fill with distilled water again, run the engine, and drain once more if the water still comes out dirty.
Close the drain valve and fill the radiator to the neck with a 50/50 mix of antifreeze and distilled water.
Leave the cap off and idle the engine until the thermostat opens and the level drops, topping up as trapped air escapes.
Fit the cap, run the engine until the fan cycles, then check the level in the overflow bottle when the engine is cold and top it up.
Tips and common mistakes
Set the heater to hot during the flush so the heater core gets cleaned too.
Old coolant is toxic to pets and people, so pour it into a sealed container and take it to a recycling centre.
Never run the engine for long with the system drained or you risk warping the head.
If the water stays rusty after two rinses, do a full superflush with a hose instead of a quick flush.
Questions
How often should I flush my coolant?
Most makers suggest a flush every 2 to 5 years or around 30,000 to 60,000 miles, depending on the coolant type. Check your owner's manual for the exact interval.
Can I mix different colours of antifreeze?
Only if the bottle says they are compatible. Mixing different chemistries can form sludge, so use the type your car maker specifies.
How do I know all the air is out?
Run the engine with the cap off until the level stops dropping and the heater blows hot. Then top up the overflow bottle after the next cold start.
This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.
