raw water impeller
 

this is probably a dumb question but in which direction should the rubber vanes be flexed during operation? is the vane to flex in the direction of the shaft rotation or away from the shaft rotation. 454 magnum big-block

Your top picture is correct. Don't worry about getting the vanes oriented correctly when changing the impeller, they will flip to the right direction as soon as the pump is turned.

put a little dish washing sop on the impeller (cheap lube)

raw water impeller
 

thanks a lot for your help