kansai pass

we would like to travel from osaka - koyasan - nara at the same day using the kansai thru pass. we understood we need to take nanaki line fron namba to koya and then cable car and a bus. are they all included in the pass? how much time will it take? how do we go back from koya to nara and can we do it with the same pass? how much time will this take?

thanks
rinat

we would like to travel from osaka - koyasan - nara at the same day using the kansai thru pass.

But note that by doing a daytrip to Koyasan, you will miss on one of Koyasan's main attraction: an overnight stay at a temple lodging.

we understood we need to take nanaki line fron namba to koya and then cable car and a bus. are they all included in the pass?

Yes.

how much time will it take?

Here you go:
http://www.japan-guide.com/e/e4904.html
http://www.jorudan.co.jp/english/norikae/

how do we go back from koya to nara and can we do it with the same pass?

Yes, it can be done by the same pass. Go back to Osaka-Namba and then take Kintetsu Railways to Nara.

Note that limited express trains of Nankai and Kintetsu Railways require a supplement fee. So, I recommend to take slightly slower express trains, instead.