HOUSTON—NASA plans to conduct a test Wednesday on the space shuttle Endeavour to see if an external fuel tank leak has been repaired.

The potentially explosive hydrogen gas leak forced NASA to scrub two launch attempts earlier in June.

Engineers think a plate attached to a vent line was slightly misaligned.

The next launch attempt will be July 11.

The astronauts are supposed to deliver the final section of a Japanese lab to the international space station.