The win at Guy’s Meadow maintained the Kirkintilloch side’s 100 per cent record and sent them five points clear at the top of the Super League Premier Division table.
Rabs got off to a perfect start when they were awarded a third minute penalty for a push on Willie Sawyers.
Kevin Green took the award but his spot-kick was parried by the diving Hurlford keeper Ally Brown. However Reece Pearson was quick to react and slammed the rebound low into the net.
United pushed forward looking for the equaliser and Ross Brash fired wildly over the bar before Darren Moffat’s header from a Paul McKenzie cross lacked power and failed to trouble home keeper Jordan Brown.
In an entertaining encounter, play swung to the other end with Pearson’s long range effort brilliantly tipped over the bar by Brown before Craig Buchanan headed a Gavin Mackie corner over the bar.
The visitors pulled level on the half-hour mark when poor defending from a Moffat corner allowed Mark Roberts time to send a back post header into the net.
But two minutes from the half-time whistle Rabs struck again with a well taken goal, Sawyers showing great awareness by turning his marker before firing high past Brown.
In a period of early second half domination Kevin Watt fired just wide following a clever Sawyers lay-off then Mackie’s powerful shot was beaten away by Brown.
Rob Roy were awarded a 58th minute penalty when Mackie was pulled down in the box and although Sawyers saw his kick saved by Brown the referee ordered a retake due to encroachment.
Sawyers made no mistake with his second attempt, sending the keeper the wrong way.
Chris Duff made it 4-1 three minutes later when he collected a Scott Walker pass before sending a stunning 30-yard shot high into the net.
With Luke Whelan pulling the strings in midfield Rabs were enjoying the majority of possession and continuing to set the pace but were hit with a late Hurlford goal in the 86th minute when a motionless home defence allowed substitute John Gemmell space and time to head the ball into the net.
However Rob Roy comfortably saw out time to extend their lead at the top of the table.