big-pond it sounds like a weak battery. The timer is made so it scales back power to the upper motor to 40%. So if a 12 volt battery is down to 10 volts it appears fine when testing. However once scaled back to 40% only 4 volts left to turn and may not do so with the weight of feed.
I have several clietns that now just buy a second battery and keep it charged with the free charger and switch every time they fill 'er up. YOu should have gotten the charger. If you do not get it fixed call me. I guess you know your wife got it from me as a surprise for your B-day
