To start things, my car has been sitting in the garage for the last year and a half. Started occasionally here and there. It needs major brake work that I have been putting off.
Today I went and started it and let it warm up in the garage. I went in the house for about 20 minutes, and when I came back out steam was shooting out of the overflow neck. I immediately shut off the engine when I saw it.
First off, could I have harmed the engine when this was happening? Also, what could have caused it? I did not see any coolant coming out of the water pump or any of the hoses.
Any help would be appreciated! Thanks, Tyler

 

It's going to be hard for anyone here to tell you if you damaged something. I'd flush the system, fill it, and run it to check operation of things like the fans, thermostat etc. Check the oil to see if there are signs of coolant, ETC.

 

No sign of coolant in the oil. I filled the system, and tried to bleed the lines, but I couldn't get coolant to seep out at first. I started it and let it run for a bit, then shut it off. I bled the lines again, and some coolant came out, but stopped after a second.
It seems that I can only get coolant to seep out of the system after it has been pressurized. After it sits for a bit, it won't bleed out. Is that normal? I'm thinking it might be the thermostat, but not for certain. I'm afraid to let the car run to heat up again.

 

You need this handy dandy radiator filler to do it the easy way.

Amazon.com: Lisle 24610 Spill-Free Funnel: Automotive

Since you don't have one, be sure the radiator is full, turn heater on, start car, open bleed screws. Air and coolant should start to come out. When it's just coolant, close the screws. Keep an eye on temp gauge as well. More than likely, the t-stat will have to open before you see any results.