Petcock

  Hey guys I took the petcock out of my 1979 kz650 ltds gas tank and disassembled it, now once it’s back together and installed in the tank fuel leaks out of the prime line, regardless  what position I have the petcock fuel flows out of the prime hose any help would be greatly appreciated 

There is no prime hose. There is a vacuum hose and a fuel hose.

something is missing or incorrectly installed.

Could be the small oring on the diaphragm valve is missing or installed too far down the shaft, Could be the diaphragm is torn. Could be the spring behind the diaphragm is missing or installed on the wrong side of the diaphragm. Could be the big oring under the lever is improperly oriented. May be other things I am not calling to mind at the moment.