Y axis stepper stalling ?

My reprap prusa i2 y axis stepper motor is stalling in the middle of printing, causing my prints to shift a cm in the y direction during printing. It also stalls during zero'ing if the axis against the end stop spring. Basically it has no force, I can stop it by barely touching it.

I'm wondering if it's a power issue? Can steppers go bad?

I have checked the bearing, lubed the shafts, tightened the belt a pinch, checked the belt bearings, checked to make sure it's not slamming into printed layers, and I've been looking online. I'm stuck...

I have a 24volt 15a power supply, but I'm not sure if I can use it to drive a Sanguinololu 1.3a, I think it said 7-30 volts, but every supply I see is 12 volt. I know my converted PC power supply is dropping my voltage to 10v from 12.2v when the heated bed is on.

Please advise.

P.s. Uncle bob thanks for your past help.

I wish I could remember all the details of each person's printers. It would make all this easier.....

Your motors should be crazy powerful even when driven with 1/4 the rated current. If you can stop the shafts with your fingers that's a bad sign. If your supply is dropping to 10V that's also not good. If it's dropping right at the supply - probably time for a change.

Your board should be capable of 24V, if you drop the voltage regulator on it. (at least that's what it says). I have no experience with that board so - no idea if they are kidding or not.

Going to 24V with 12V parts is not a real good idea. You would need to switch your heated bed and extruders over to 24V. It's not hard to do, just don't plug the 12V stuff into 24.