Goldstar GVR-DD1 The motor which drives the FF. RW. and play tries to but will not work. This motor will work when tape is ejected. Is a diagram available of view of bottom of player. It is impossible to get a visual look since the circuit board is adhered to bottom of player. Since the arms to move tape up to head for play position do not move, I am wondering if there may be a missing/broken part, timing of cams, or broken belt. Could you help? Mark

Even the service manuals are pretty bad at helping with mech problems like this. You just have to be very mechanically inclined to figure it out. A lot of VCR mechs are very similar however so this is where experience helps. You do need to get the circuit board off however. Usually a few screws up from the bottom. Pretty smart huh! - put the least reliable parts (the belts) in the hardest place to get to. Look carefully for little broken plastic pieces. gear teeth etc. Since the motors work some of the time, they are not the problem. Could be the mode switches are out of time. They are a set of switch contacts buried in the mech which tell the brain what position the mech is in. Move the load motor by hand (I use a 5V power supply with a fwd/rev switch so I can run it back and forth and watch the action.
Goldstars are good mechs. They make a ton of them and pretty well get the design bugs out, but of course those little plastic parts break easily.
Hope Ya Fix It.