Cannot loosen or tighten a loose impeller blade bolt on a ryobi leaf blower, rgbv3100

See spare parts here: http://www.ereplacementparts.com/ryobi-rgbv3100-41asgbpg034-handheld-blowervacuum-parts-c-7931_15636_18678.html
Sears provides a manual but lines are not specified: https://c.searspartsdirect.com/mmh/lis_pdf/OWNM/L0404046.pdf
This video may also be useful: https://www.youtube.com/watch?v=D3lmi3rtmh0

Bolts rotate counterclockwise to tighten so go clockwise to remove.

...and then what?

might find that it's a left handed thread, as they often are.

Is definitely a left hand thread on the bolt...your machine came with a small rod to hold the head while loosening or tightening the nut which holds the blade....there is a hole and a slot in the machines head to insert the rod....if you've lost it you can probably use a small piece of drill rod about 5/16 diameter or a drill bit to hold it ...turn nut in clockwise direction and it will probably come loose....good luck !!! ;-D

try changing the fuel lines around and try again its easy to get the wrong

It is right handed, counter clockwise to remove

test for spark.
while spark plug is out - put finger over hole see how much compression there is.

If good spark - look for holes in fuel line.

you take a screw driver and put it in between the flywheel fan teeth then unbolt the fan bolt for the inpeller

There may be a push button type blade lock, and on many of these saws the retaining bolt for the blade is backwards threads, e.i., looking at the top of blade retaining bolt, turn it clockwise to loosen. This would normally tighten, but in the case of many of these saws, it loosens it.