Gets hot and stalls out

The more correct way would be to replace the leaking heater core.
I'm in 100% agreement, but for now I'll have to loop them and cap it off at the firewall. I just found out that my significant other is going to be transferred to Houston and I'm in the middle of a full blown renovation of a house that we'll now likely never move into, plus work travel, vacation travel, and a rental property that needs a renovation now that the tenants have moved out, so my hands are pretty full at the moment.