Rubi, if you pull the regulator out and find that big external spring is broken, as Shopkey implies, absolutely replace it. If that external spring is not broken then your real problem is inside the regulator. There is another internal spring which you will find is broken (the small tab on the end of the spring). My first picture shows the reassembled regulator but note I’ve rebuilt it with the housing held together with nyloc lock nuts. You are going to have to get creative (wear safety glasses) and drill out the original rivets holding the housing together to gain access to the real internal problem. The next picture shows the replacement internal spring, about the diameter of a quarter. Classic Parts, (1947-54) Window Regulator Spring Item Number 18-781. $3.95 each Good Luck. Dave
