I need to know what I can expect from a bad water pump - what are the signs?

KASR

 

I guess the only things that can really go wrong with water pump are gaskets and bearing.

If a gasket goes bad, that makes the coolant leak from the pump. If a bearing goes bad, it usually starts to make some noises.

TS

 

if it were bad, would the engine overheat immediately or slowly?

KASR

 

a coolant leak and smoke coming from under your hood. Also a funny burning smell. In terms of how the engine would overheat it really depends on how much coolant your leaking. If its just a little then your engine is still running a lot of coolant and is cool. If your leaking alot then you dont have much coolant and will overheat extremely. If you ever see smoke coming from under your hood stop driving it and get it checked out.