I have an old (15+ years) REI Clipper tent.  I set it up in the rain the other day to test it out and I had leaks in the rain fly.  Does anyone have solutions for this?  I was thinking of scotchguarding inside and out.  Thoughts?  Yes, I know it is an old setup.  Yes, I know I could replace it, I already have.  I just want to know if I could do anything to re-waterproof the rain fly.