Hi...I picked up a KT K85G2 from an estate sale. The KP500V pumps has a small valve mounted on it with a 2 wire connecter that plugs into the ecu. The previous owner cut the lead off right at the coil so i assume he was not using this feature. I ordered a new one from KT but i was wondering what exactly is it doing because the fuel pump works with it disconnected? im guessing it must fail open for it to be allowing fuel to pas thru it.
thx

That's a priming valve, it connects to the ECU, that doesn't affect fuel pumping, its used during start up.

https://drive.google.com/file/d/1sxm...HnFjnNeo2/view

Is it actually used during every turbine start or is it just used to prime the fuel lines when the fuel line is empty (e.g. right after you build the fuel system)?

There is a brief description in the the manual. My understanding is during the glow warm up the valve closes and the pump runs briefly only circulating fuel within the pump to get it primed for the start. The valve would normally always be open and only powered closed during that quick priming sequence at startup. Probably helps the start up go smoother but not really a critical if its not working.