A preconditioning scheme for the stabilization of microchannel plate (MCP) Z stacks has been developed. Vacuum baking of MCP Z stacks is shown to have little effect on the gain and pulse height distribution characteristics, but tends to increase the background event rate. The major outgassing components during baking are found to be H2, N2, H2O, and CO2. The MCP stack resistance is found to decrease as the temperature rises, and the temperature coefficient has been determined. Burn-in of MCP stacks is shown to cause a 3x to 10x decrease in gain and also results in minimization of the background event rate. The major outgassing components during burn-in are found to be H2, N2, and CO2. Stabilization of the MCP stacks has been achieved when 0.06 to 0.08 Coulomb cm-2 have been extracted from the MCP stack output during burn-in.