Booster pump (PB4) seal leak

[AmigaDude]

OK, someone has to let me in on this secret: How do you remove the impeller? I put a wrench on the motor to hold it, but cannot get the impeller loose even with a strap wrench.

[vgg659]

I put a pair of needle nose vice grips on the motor shaft to keep the shaft from spinning, and simply unscrewed the impeller with my hand. I do not remember the impeller being reverse threaded, but maybe that's the problem.