United registered another good away win on Saturday morning despite being faced with difficult conditions.
The Blues took the lead through Sam Fishburn early in the game but the Ammies pulled it back from the penalty spot just before half time.
Ryan Carr restored the lead after the break, and Fishburn notched his second to seal the points after DJ Taylor had been toppled inside the box with just minutes left to play.
Youth boss Eric Kinder said: "If we're being honest this was a poor, scrappy game played in difficult conditions.
"We never really mastered the astroturf surface and the wind was terrible.
"However, yet again the lads have dealt with it and found a way to win.
"They've defended when they had to, taken their chances and overall deserved to to take the three points."