I was recently chatting with another river enthusiast, it's better to call a well respected artist "river enthusiast" than a river rat, discussing the AQ's bad habit of breaking shafts. My father once surmised the cause was that the engineers don't use the valve jacks while handling the boat and setting the engines to come ahead or back. Not using the valve jacks to release the pressure on the pistons and torqueing the shaft was as bad as keying the boat's pitmans while on center, not blowing down a high pressure boat's mud drum often or for a long enough period of time, or not carrying the boiler water high enough. All of these being a recipe for disaster to an old time steamboat engineer.

In the back of my mind I remembered what Alan L. Bates wrote in his magnum opus BELLE OF LOUISVILLE: Ohio River Steamboat published by Howell-North Books; Berkeley, California; 1965. So on page 92 he writes about:

Handling the engines is no mean trick. To shift the engines of the BELLE from a forward motion to backing involves several operations. First, the throttle must be nearly, but not completely closed. Next the admission valve levers (valve jacks) must be lifted so that the steam may pass through the engines to the feedwater heater. Can't afford to chill the heater or the boilers, you see. Then the reach rod must be lifted so the yoke engages the upper pin on the rocker arm shaft. After that the admission levers are lowered to the rocker arms and the throttle opened. It is opened quite wide to start the heavy wheel rolling and is throttled to the desired speed. After all this the engineer must move the telegraph handle to let the pilot know that he has understood.
This must be done each time the pilot calls for a change of direction...

I thought that I would bring this up as some food for thought, and see what others more knowledgeable might have to say. Dan, Mac, Steve, Kenny, Tom, Scotty, or Chris are you listening?