Here is a close up of what came up when I raked. Thanks

Short answer is that fescue is not known as a thatch producer.
Your pictures indicate dead patches that probably arose from the winter weather. Winter burn or snow mold rather than damage from what is generally considered thatch. Also investigate alternative reasons like random hydrophobic patches and apply extra shampoo treatment to those areas. You can overseed, but you will need to give extra care to keep those areas alive through the summer.

This post was edited by yardtractor1 on Mon, May 5, 14 at 10:59

I would stop raking. It isn't helping.

Grass growing near pavement is always subject to heating in the night as the concrete gives off drying heat it absorbed all day. Be sure you're not getting runoff right there. It looks like the soil is sitting up higher than the sidewalk. That's not great. I suspect your predecessors in the home felt like then needed to apply 1/4 inch of topsoil every so often. That's not a good idea for a couple reasons. Also in the snowy places grass near pavement sometimes get salted. That is not good either.

I would keep doing what you're doing. Did the soil get softer with the shampoo? Try sticking a screwdriver into it. Seed if you must but don't expect miracles this late in the season. Fall is a much better time to seed cool season grasses.