Magnavox D 8443 basket case

My most recent heap is a the 3 speaker Magnavox I picked up cheap. many issues with it, the most puzzling is the tape deck. the on off button seems to play the radio when it is off, and the the tape when it is off. the tape does nothing. unless I push a button with the radio on, turn it off and it spins for a split second. so the motor works, it has power... what is good to use as a cleaner in the mechanical area of the tape deck? and any thoughts on what to check for the tape issues. also, couldn't get the line in to work, but, how would I turn it on with that strange power set up?
thanks guys.

edit, the on off button plays the radio when it is on, the tape deck im assuming when it is off. and the line in? who knows.