reseeding thinned lawn
 

I am trying to reseed part of my lawn which has been thinned out. I
have tried to rake the area. However, since there are alive grass on
the area, raking did not help me get to the bare ground. I mean after
raking (to a great deal), I still could not see the bare soil. I did
not want to rake more as I thought that it might root out the live
grasses. I spread the seeds + startup fertlizer, and water the area. I
am not so sure what I have done will work out for me.
Can you let me know of what you think of my plan? If I want to get a
thick lawn, should I root out all the grasses (alive and dead
together)? Should the grass seed touch the soil for sure?
I am in Canada (Zone 3). Temperature is moving around 25 C. Do you
think that time is fine for lawn reseeding?

thanks

Could you rent a dethatcher? What type of soil do you have? Maybe your
soil needs to be improved before over-seeding? Grass seed needs to be
at least touching the soil, my mother-in-law likes to bury it under
about a 1/4" of peat of fine soil. She has the best luck too.