Why is radiator coolant still green after multiple flushes?
Old coolant can leave lingering discoloration and residue in the system that takes multiple repeated cycles to clear out entirely. This uncertainty makes it difficult to know when the flush is actually complete and whether the system is fully cleaned.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Accepting the current flush condition as good enough
- 2Repeating the flush process multiple times
- 3Removing the thermostat, lower radiator hose, and heater core hose to run a garden hose through
- 4Planning to perform a complete flush of the system while replacing the compressor, condenser, and expansion valves.
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“From videos I seen I expected to see muddy but clear water. Not greenish.”source ↗
“Complete compressor failure on my 200k mile 2015 Sienna. Had the refrigerant drained and found flakes in the filter on the bottom of the drier.”source ↗
“I’m here looking for advice on the flush from the firewall to the trunk. Those are long lines with lots of curves and an evaporator somewhere in between. I’d rather not take apart the dash if I can help it - can I reliably flush that whole system without taking the lines apart?”source ↗
Where this came up
People with this problem also raised
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