How do we really know?

In the days gone by, for longer movements of steam engines "dead in train," the side rods were removed, leaving just a wheel rotating on an axel, creating nothing more than a very heavy freight car. Rare these days.

With most engines plying main tracks these days, they are usually equipped with modern (26L) air brake control schedules, so mu-ing is not a problem. These days most engines, if dead, are handled "Dead In Consist" (DIC). There can be instances where an engine is moved "Dead In Train" (DIT) Here, there is a feature in the air box called the "Dead Engine Feature." When cut in, it re-routes air through different ports and passages that allows the air brakes on the engine to behave just like a freight car control valve is telling it what to do. In addition, that engine DIT must be entrained in the last ten cars in the train, unless it has changed.

For a drifting steam engine:

1. power reverse full (in the corner) in the direction wanted

2. open drain cocks when starting, then close

3. light throttle (more for the lubricators than smoke box draft. The fire-boy has a blower at his disposal, but you're drifting anyway)

4. engine brakes are released when running and auto air is cut out unless controlling the train from the engine on the point.

Steam engine cross compound air pumps, which actually are amazing little machines in their own right, are not even close to putting out the volume available with modern, two stage, three cylinder, water cooled air compressors, (nominally 254 Cu. Ft. / Min. at full rack [900 rpm]) so their input is zero to less than zero. Like a flea on an elephant's back, and I would expect probably cut out when mu-ed with diesel electrics, tapped into their main reservoir, and saving time on the pumps. There's not a lot of 'em around and I'm told parts can be hard to find...

Well i'll take a stab at this.A steam engine is basically free wheeling when the throttle is closed(or at least so i've been told).Samurai will be able to answer this better than i can as he has fired on steam engines.Steam engines didn't have "MU" connections to be hooked up to diesels except for air.Most of the time you see a diesel behind a steam engine it's there in case the steam engine needs a bit of help on a grade and for it's dynamic brakes going down a grade.The diesel wouldn't need the help of the steam engine in the case of the engine brakes(or for main reservoir air either).We don't really use the engine brakes anyways til we actually come to almost a complete stop(new AC units have dynamic almost to a standstill).As for a free wheeling diesel the traction motors wouldn't be putting out any voltage.When a trailing unit is isolated the generator isn't doing anything.Without excitation to the traction motors they are doing nothing.