My 1975 w115 power steering went out today. I opened up the hood and it seems that all the power steering fluid leaked out either from being pushed out the top of the reservoir, or a faulty hose below. Is there anything damage that could be caused to the car by driving it without power steering for a couple days?
You had P/S fluid in there as evidenced by the bath your engine took.
Chances are the fluid was low.
What happens next (was avoidable) is that the existing fluid gets mixed with air sucked in by the pump (because of the low level) and the foamy mix builds up pressure.
When you turn off the car it gets released through a small vent hole in the P/S pump reservoir cover.
You probably have a slow drip somewhere and the level drops over weeks or months.
This system will take Dexron automatic transmission fluid (generally cheaper than PS fluid).
Fill up the PS reservoir with engine off.
Start the car.
The level will drop immediately as the system is almost empty, keep it (PSRes) filled.
Move the steering just a little bit to get the level to drop further and fill again.
Turn off car or better: top up the reservoir while car is running.
You probably need less than 2, possibly one quart of fluid.
You can and want to purge all air out of that fluid.
If it is red and translucent , then you're fine. When it turns pink and with tiny bubbles then you're not.
Make sure not to let it draw air or you'll have the same mess again.
Check fluid level every couple of days until you can figure out how much it uses/looses.
Chances are that the leak/drip is on your Steering box.