So irritating and frustrating...
The wet spot on the driveway. Smelling Anti-freeze. Having to refill the overflow tank every few months.
Had to find the problem.
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The Toyota thermostat housing 'O' ring where the parts join; upper right quadrant, there was my leak.
Then I looked down...
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Replacing the timing belt, the radiator was bumped, maybe by a wrench.
Eventually, expansion and contraction opened the hole and,
although the yellow color Amsoil Propylene Glycol Antifreeze and Engine Coolant can stop itsy-bitsy leaks, this became too large.
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Perhaps, the tiny hole in the center tube.
I suppose the moral to the story is; Do the job right and...be careful.