[ronstory]

It does not take much force on the impact drives. Just spin counter-clockwise on the screw to take up any slack in the rotation before you whack it.

Interesting. Who makes an electric version? I would be curious of the design since with a waterlift muffler, the flow likely needs to vary with engine RPM. With one a constant speed, you could risk flooding the motor due to not enough exhaust pressure (eg. idle) or alternatively too low of flow for high RPM cooling.