Here's a picture of the setup on my 515, It matches the center picture you posted. I have never seen the lower setup before, although it looks very interesting
The shut off is attached to a rod that goes down the inside of the pump body and comes out with a lever next to the drain back pipe. It shuts the valve when you insert the nozzle and lock it in the drain back tube
Last edited by 42packard; Mon Nov 06 2017 03:01 PM.