I have a 1971 coupe with a lazy window. It is a hand roll-up crank window and not an electric window. The problem is that after I roll the window all the way up (fit is good), the window goes back down a quarter inch after a few minutes or when I go over a bump or shut the door, etc.
Any suggestions how to fix this?

 

IMO:regulator worn out, take door panel off and then find problem, correct problem, problem solved! How is this considered LAZY? I would think it would "hardheaded" since it would not do what you want it to do. Window probably needs taken apart and lubed, worn parts need replaced, etc. NOT a hard job to do, just takes time & money for replacement parts, if regulator is worn out, "originals" can be found here on the forum in WTB parts section. Information on taking the windows apart can be found here also. IMO

 

Doesn't regulator imply an electric window?

 

This won't cure it as has previously been mentioned the regulator is worn, but with the window all the way up remove the crank and position it at 5:00 or so and that should keep the window up.

 

No. There has to be a regulator whether power or manual.