If you are saying that a freeze plug failed the size depends on which one it is. There are multiple sizes as well as threaded plugs and simple cups. 3/4 inch, 1.5 inch, 29/64" and 53/64 inch. If it failed due to corrosion then I would likely replace all of them as the rest are probably in no better condition.
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Tuesday, June 12th, 2018 AT 3:50 PM