Hooking up air lines to Mamods "Have read that this is not a very wise thing to do."
Perhaps due to:
Wet steam does provide some lubrication while dry air does not...
I can only speak for myself, before applying any air I oil everything up well and I run the engine only long enough to make adjustments, check for leaks and see how it performs usually a matter of minutes.
If one was not applying air to the boiler but directly to the engine an attachment to the compressor line could supply oil to keep it lubed.