A spacewalk completed by astronauts Scott Kelly and Kjell Lindgren to reconfigure a prior coolant leak went mostly trouble-free on Friday. A leak of ammonia was rerouted back to the main radiator that is used by the International Space Station’s solar arrays, bypassing a second radiator from three years ago which was created to identify the leak.

CBS News reports that the secondary radiator was originally folded up alongside of the power truss. It was later opened up when the astronauts ran out of time to bring it back down. The goal of the spacewalk, however, was simply to restore the cooling system to its original configuration.

In addition to correcting the leak the space walkers also adjusted the break handles of a carrier designed for equipment and tightened bolts on a strut near the carrier that was vibrating due to being loose.

The space walk lasted approximately seven hours and 48 minutes. The total space-walk time by astronauts on the International Space Station is just under 2,000 hours, since the station began being assembled in 1998.

The coolant repair was the second space walk conducted by Kelly and Lindgren in under two weeks. Their last walk conducted routine maintenance and laying down new cables that will be required by future docking systems.

The mission Friday was a bit more difficult, as the two astronauts had to reconfigure a cooling system that was running on a secondary radiator for almost three years. The leak that forced the secondary radiator to be used was caused by a pump that needed replacing. Since then, engineers have wanted to reconfigure the original radiator so the secondary can be used in the event of future issues.

The process took longer than expected, forcing Kelly and Lindgren to leave the second radiator un-cinched, and uncovered. Doing so would have added an extra hour and a half to a project slated for just over six hours. Leaving the radiator deployed is considered more structurally sound than closing it unprotected.