CAPE CANAVERAL, Fla. (AP) — NASA has fueled its huge moon rocket for the first time and completed a countdown test despite a fuel line leak.

This was NASA’s fourth crack at the all-important dress rehearsal, the last major milestone before the moon rocket’s long-awaited launch debut.

The previous attempts in April were thwarted by a fuel leak, as well as stuck valves and other technical issues.

A leak in a fuel line almost curtailed Monday’s test at Kennedy Space Center in Florida. But NASA managers decided to go ahead with the countdown test after loading the rocket’s tanks with fuel.