Coolant is flammable, at least the older glycol and polyethylene glycol forms.Again, coolant is NOT flammable. If coolant enters the combustion chamber it will serve to prevent combustion, not promote it. You can try it yourself. Start a fire in a trash can and pour coolant on it. What do you think will happen?
I've never heard of an engine fire caused by coolant entering the combustion chamber. If you have a documented example please share.
https://firefighterinsider.com/antifreeze-coolant-flammable/
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