A vascular closure assembly is configured to seal a vascular puncture in a vessel. The vascular closure assembly includes a balloon location device and a sealant delivery device. The balloon location device includes an inflation tube and an inflatable balloon positioned at a distal end of the inflation tube and operable, when inflated, between a first position blocking blood flow through the vessel and a second position sealing the puncture from within the vessel. The sealant delivery device includes a sealant delivery tube having a first lumen sized to advance over the inflation tube to the puncture, and a second lumen configured to deliver a volume of sealant to the puncture. The first lumen may include a rapid exchange feature.