I have a Hamilton 940 that runs great but has a weird issue. It sets perfectly with the lever pulled out, but when the lever is pushed back in, the watch winds by turning the crown clockwise just as it should, but, if I turn the crown the other way, the hands move backwards. What could be causing this and would it be easily fixed? There also seems to be no spring tension on the lever at all. It pulls out very easily and slides back in the same way without retracting itself at all.

Can,t say for sure without seeing under the dial but could be dry gummy grease,, there is also a spring that moves it from setting back into wind postion that can and does break on the 18 size hamiltons.

I can also tell from what you say that your shipper spring is broke it is what keeps tension on your set lever to snap it back in wind postion.