We have a 4160V starting motor with torque converter for our GE frame 7EA combustion turbine. We recently upgraded the Mark IV controls to the Emerson Ovation system but it appears that the problem would have existed in the Mark IV as well. When a start is cancelled with a normal shutdown before the turbine reaches starting motor cutout speed of 60%, the turbine does not fire down because the starting motor is still engaged at full torque and holding the speed at about 1100 rpm's. This appears to overheat the starting motor windings with the long duration at full torque. It seems that the starting motor should cutout if it hasn't already when a normal stop is given. My first concern is if we modifiy the logic to do this, will the fuel have enough time to ramp down to flame out before the speed drops too low? Does anyone know why the MarkIV would not already do this?