I have an 02 silverado 4.3 with 116k , yesterday the anti freeze started pouring out of the front of the engine , from behind the water pump , or at least that what I can see, it is not seeping , it is pouring out as fast as I pour it in , never seen this, have any of you ??

 

It's probably coming out the Vent Hole, just bite the bullet and install a new Pump.
I am surprised that it started so copiously. Usually they seep at first.

 

The 4.3 also has 2 small hoses at the top of the water pump. It could be one of them and it would look like from the back of the water pump.

 

I believe that oldchevy still means that you should replace the pump

 

Yes it could be due to pinches in the hoses or may be bcs of pump worn out. So you just need to replace it.