| so it looks like the common denominator with the two fan detonations is that 2-month old water pump. or at least the installation event. if your water pump bearing failed it may have introduced a wobble. or it could have been bad installation technique (like not properly re-clipping the radiator).
although it's not necessary to touch the radiator, when they changed the pump (2 months ago), did they remove or in any way manipulate the radiator for pump access? even if the fan or anthing sharing the drivebelt has no wobble, the radiator could have been loose (held on only with clips). the fan does suck the radiator toward it.
i doubt the parts store will claim any responsibility for anything other than the failed water pump. they may say you can't prove the water pump caused the fan to grenade.
how is it running with the new (week old) water pump?
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