icanfixall
Official GMM hand model
I'm going another direction on the sucked in top hose. Lets look at it has started pulling a vacuum on the top hose. So the pump is able to suck plenty of coolant. Reason I look at it this way is the top hose is sucking flat or near flat. So where is thew rectriction to flow. Could maybe be the radiator. We do not know how many tubes. How many rows or much more. Its just asumed it ok because its new. But could it maybe be underrated and not able to flow enough?? Flushing is a fair idea. Doing it with the old radiator is ok too. But if you had the same issue with the old radiator things wont change. So I'm not sure changing the water pump is going to do much if anything for you.
Now about the recovery tank and hose. These systems make enough pressure to force coolant out of the system. But they REQUIRE a clear hose and a tight system to suck it back thru a closed radiator cap. May want to install a hose clamp on the hose to radiator cap neck end of the recovery hose. Might need to remove the hose from the radiator and blow.. Don't suck thru it but see if the line is clear. They do crap up from time to time. Then coolant or what resembles coolant can be forced into the recovery tank but it can't be sucked back. Hard to believe till you prove it.
Now about the recovery tank and hose. These systems make enough pressure to force coolant out of the system. But they REQUIRE a clear hose and a tight system to suck it back thru a closed radiator cap. May want to install a hose clamp on the hose to radiator cap neck end of the recovery hose. Might need to remove the hose from the radiator and blow.. Don't suck thru it but see if the line is clear. They do crap up from time to time. Then coolant or what resembles coolant can be forced into the recovery tank but it can't be sucked back. Hard to believe till you prove it.