hey guys today my slivertop 20valve 4age shat another water pump this afternoon only installed my other one bout 3months ago( thank god still under warranty) it has cracked in the exact same spot which leads me to believe i have a underlining problem
this is were it cracked
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want to know
A is this a common problem?
B any ideas has to whats causing it??

im thinking either the pump is flexing from the vast amount of engine vibration which my has a lot of due to tuning issues when cold...
or its my fan ( which i intend to get rid of in place of new rad and twin thermo setup)

this water pump was not a genuine toyota one either was a cheap brand but getting a new toyota one ordering it 2moro

any help i would be grateful