Flare? you mean light leak?
Scratching?.... Clean all the surfaces the film will come in contact with using denatured alcohol. The 2 very thin rollers should be free n the tabs slightly above the film gate height... they tend to get flattened over the years.
Check the frame mask that all screws are tight and for debre that may scratch the film as well.
Another overlooked sourc of scratches is taking the film off it;s backing and loading the reels... not always the camera's fault.