It confirmed the two club's promotion positions last season, when Carlisle failed to beat the Londoners in their two meetings but went up as League Two champions, with Orient going up in third place.
Orient manager Martin Ling has come out on top in the last two meetings between the sides at Brunton Park. But his Orient side were second best from the start.
Keeper Glyn Garner pulled off a great 16th minute stop to prevent Chris Lumsdon from giving Carlisle the lead, turning the midfielder's fierce 18-yard effort over the bar at full stretch.
But he was given no chance when Carlisle strung together a tremendous scoring move midway through the first half.
Michael Bridges opened up the Orient defence with a pinpoint diagonal ball for Gall, who showed blistering pace from the halfway line, before curling a 15-yard shot beyond the Orient keeper's reach.
Garner blocked a Peter Murphy header at the foot of the post before Keiren Westwood was called into action in the 47th minute, smothering a shot from Lee Steele.
But Orient created very little and Carlisle went further in front three minutes after the break.
This time Gall was the creator with a back heel for Karl Hawley to scamper into Orient's box and poke the ball past Garner.
Playmaker Bridges was causing all sorts of problems for Orient, with Chris Billy, Lumsdon and Paul Murray taking a firm grip in the middle of the park.
Billy fed Bridges on the edge of Orient's box in the 59th minute and Gall was on the end of another inch perfect through ball that left the Orient defence playing statues, to score his second.
Just three minutes later he was presented with the chance of a hat-trick when John Mackie sent Hawley sprawling near the byline with an awkward challenge to concede a penalty.
Gall hit his spot-kick to the keeper's left but at a height that invited Garner to turn it round the post, which he did comfortably.
After a triple substitution Orient perked up a bit with Steele pulling a headed goal back in the 67th minute and Westwood saving a fierce Donny Barnard shot.
However the Londoners have now leaked six goals in two away outings and have to be worried about the rest of the season.