APU suckin' sand?

PS: The Preventive Maintenance Monthly, Dec, 2004

Mechanics, repeated Black Hawk engine start-ups suck air into the APU. Unfortunately desert sand gets in the mix, clogs the APU and causes the engine control valve to stick open.

When that happens, the APU does not shut down, and the No. 1 and No. 2 engine starter valves don't close properly. It continues sucking air and sand. Then the starter light comes on in the cockpit, and an engine shutdown is the usual result.

HERE'S A SIMPLE FIX TO REDUCE ENGINE START UP PROBLEMS ...

Open all aircraft doors, cover the center console and turn on the heater and vent blowers. All the trapped sand will blow out all the ducts.