Guys
Just fitting a new water pump,removed old one and noticed the small hole on left hand side was blocked both on the block and pump,cleaned hole on block the best I could,what is this or where does it go and would it be ok to give it a last with some air to make sure it's not blocked.
Just fitting a new water pump,removed old one and noticed the small hole on left hand side was blocked both on the block and pump,cleaned hole on block the best I could,what is this or where does it go and would it be ok to give it a last with some air to make sure it's not blocked.

