And DON'T USE REGULAR SIMPLE GREEN. It isn't aluminum safe. The Extreme Simple Green that says OK for aluminum obviously is. YES, hydrogen embrittlement is an issue with aluminum (so says my A&P general textbook)

Jeff Hersom
N3740J '67 150G "Gremlin"
N8634S ‘66 150F/150hp “Rusty”
Hangar W-6, Helena Regional Airport
Places I have landed Gremlin:
[Linked Image from visitedstatesmap.com][Linked Image]