Overheating 2011

2011 Aveo Sedan overheats. No heat output. I can feel a tiny bit of heat coming from the vents if I rev the engine. I fought my way to the water pump and it looks fine to me. Impeller is intact and tight to the shaft. Should I see flow in the expansion tank? I don't know Aveos, but I assume a stuck-closed thermostat wouldn't block flow to the heater. And I think the thermostat was replaced somewhat recently. Could something be clogged?

And does anybody have a part number for the water pump seal? I can only find the one for the timing belt driven pump. This pump is driven by the serpentine belt. I guess I could just use RTV sealant on the old seal.

Regarding the water pump seal/gasket for 2009-2011 Aveos, you won't find one. Doesn't exist. If you want the gasket, you have to buy it together with a new water pump. I myself have also looked for the gasket only for the 2009-2011 Aveos, a spare one, just in case I screwed up installation of a new water pump. But they don't exist.

Deano

You won’t see much, if any flow in the expansion tank.
Over heating with no heater core heat just makes me think of a cracked head or head gasket failure that just eats antifreeze.
Another possibility is a clogged cooling system. If Dex cool was mixed with non compatible coolants, it could cause goopy antifreeze. I only mention this because when dexcool first came out, people would just use regular green antifreeze to top off, or fill 1/2 of the system when an upper hose or thermostat was replaced……bad things happened.

I haven't seen any other evidence of a blown head gasket, but I know that a possibility. I guess I'll flush the system and see what comes out.