Help with putting petcock back on!!!

I bought a 1984 KZ550 ltd. The gas tank was not attached. The screws were missing so I ordered new ones for the petcock,fuel sensor and the tank itself. The screws don't want to go in for the petcock and sensor. The old screws won't go in either. Can someone tell me what im doing wrong. Is there a trick?

Can you post a pic of the area your talking about. Maybe run a tap through the holes.
Mark

Oh yeah, welcome to the site.

Sounds like you have the wrong size screws. Im assuming the screws dont fit with the petcock off the tank. If yhey do fit without petcock than you have the wrong petcock.

I don't have a camera to take pix. I order from cycle parts nation. The screw matches the old one that won't go in either. Should I grease them up.The screws are going into the gas tank. These are Kawasaki OEM parts.

Newbie, A quick peruse of my micro-fich indicates sensor screws to be 5mm, and petcock 6mm. a wild assed guess is PO tried to use american bits and boogered threads.try chasing threads w/ proper taps. make sure spacing for both are correct. luck g