Still Able to Reinsert New Idler Tensioner Pin After Removing It?

2001 Tacoma 3.4L 5vzfe 110k+mi:

I am in the reassembly stage of a timing belt/water pump replacement. I've installed a new oem tensioner. Pull out its pin. Even after 1 hour, I can still reinsert the pin. Turned the crank 2 revolutions and all 3 timing marks on cams and crank lined up. The belt seems to be as tight as before installing the tensioner.

Is this normal? Or is there something wrong with the tensioner?
Or does the tensioner kick in and start to increase tension after the belt slacks a bit initially when engine is on after completing the project?

thanks

 

Probly this. I remember mine didn't move much when I pulled the pin.

 

Ok thanks. I'll ignore my observation and continue with the reassembly [hoping the rain stops soon].