Trouble shooting this old compressor
Hi I recently was given an old air compressor from my friends work but it had a few parts missing. I recently got the small black hose replaced (because it was cut) but now when I turn it on air comes out of the bottom of the container where the pressure gauge is (see photo). I am not sure if i need anymore hoses to connect to this container or whether I just need a steel end cap for it to seal off the container. Any help is appreciated.
Also, I am fixing it to sell it. Does anyone know what something like this should be worth? I think it is either a 2.5 or 3hp.