What is the weep valve for? What function does it have to the waterpump circuit?

Weep hole leak usually means water pump is leaking and often due to bad bearings and seal.

It is the water pump, i would buy a new thermostat also, you can buy a water pump that comes with a new stat and housing, that is the best way i think and that is the way i do them.

These water pumps are big looking but are very easy to replace, i will tell you that when they leak it is very, very hard to see the weep hole, the area you say yours is leaking is the pump so sure, this waterpumps leak at the mating gasket where the pump meets the block or weep hole, any way it is the waterpump.

you will see the new one , how they put the weep hole it flows through the housing to leak out when bad but hard to see.

hope this is helpful.

Visually inspect around bottom of waterpump. There's a "weep" hole - it's an early warning system for waterpump before bearing seizes. Also check passenger carpet/floor up to firewall - possible heater core leak.

THAT SOUNDS CORRECT! THE WATERPUMP HAS WHAT IS CALLED A WEEP HOLE! IT IS LOCATED ON THE BOTTOM OF THE WATERPUMP! IF THAT IS LEAKING, THE WATERPUMP WILL NEED TO BE REPLACED!

Possible leak areas waterpump, heater core, intake manifold gasket, radiator or hoses. Waterpumps have what they call "weep holes" which is an early warning system to prevent major damage when pump fails. The weep hole needs to be inspected from below and is usual behind waterpump pulley. If it's your heater core, you should smell anti freeze inside truck and in most cases windshield will fog up. Radiator could be pin hole to front side of radiator (which is buried behind AC condenser & grill) and if it was head gasket, intake manifold symptoms would be coolant in oil OR lots of white smoke from exhaust. Try parking it on a clean dry surface and see if you can narrow down area where leak is coming from.

By water I,m guessing it's actually coolant. the most common cause would be a waterpump seal. there is usually a tell tale hole on the waterpump cover that will weep coolant if the seal is failing. Other causes can be a leaking head gasket but you will generally notice a change in performance.

That means that the pump is bad and will need replaced.

This is called a weep hole and it indicates the rubber seal is now leaking antifreeze onto the waterpump bearing and it's only a matter of time before the waterpump falls change the waterpump.

while your car is running and, warmed up; squeeze the top radiator hose; if you feel coolant flowing your thermostat is open and your waterpump is working if your waterpump fails it usually drips coolant out of a "weep" hole on to the ground first.

are you calling the bleeder valve the weep hole in the bottom of the pump?  If it's leaking you need a new pump.