Good for you, don't stop now; keep going.
Plug in the washer and let it run for ten minutes or so without agitation. Then engage the agitator for ten or whatever minutes. Am guessing this machine has been sat sitting for a very long time and things have or had seized up.
If you can drain the tub manually (simply lowering the hose to floor level) and either don't mind a bucket brigade and or have another way to drain; fill the tub with hottest water you can, then go with the above advice. Idea here is to get things softened up (in particular the various lubricants), and flowing.
Happily Maytag built these machines like tanks and to some extent over engineered them for their purpose.
Service manual (available onsite from the library), tells how to detach and dissemble the pump for cleaning, trouble shooting and or repair. If the thing is also "jammed" it could very well be years of not dissolved detergent/soap, crud and God only knows what else has dried into a mass that needs cleaning out.