Problems with noise, heat bed temperature and no X / Y endstop sensor on Makerbot Replicator 2X
First, your Y-belt is way too loose! (seen at the beginning of the first video). It is so loose the idlers barely grip onto it!

Second, the X-endstop metal pin is loose, seen at 1:22 of the first video. Could be that the endstop is not working. Maybe you can hook up your printer to USB, you can then send direct commands to the printer, e.g. M119 will report the status of the endstops. Sending this code multiple times will alternatively pressing the endstops manually you can find out if they work. 

From the second video can be seen that the nozzle to bed distance it too large, and if fixed and still not adhering you need to apply an adhesive (hairspray/glue stick/or 3D print adhesion spray).

This printer is in need of some serious maintenance! Depending on your technical skills this may be a challenge!