Single shot SKS

[eng208]

I have a Yugo SKS that is a single shot right now. It belongs to a friend of mine and as far as I know, it has never operated right. It is just like the one pictured below, http://forum.gon.com/showthread.php?t=338504 , and has a selector on the gas tube. I have tried it in both positions, and the piston is not driving the bolt out of battery. The gun is clean, and properly lubricated. Any ideas what I can do to fix it?
Thanks

[ISC]

Google Yugo SKS problems. It's very common and usually can be fixed by replacing the gas valve and/or the piston or gas tube.

[eng208]

Fixed it just now. Took the gas block apart and cleaned the port out with a drill bit, then cleaned up the selector piece that goes in the gas block. Got it to line up properly, it was just a little bit off. Now it is reliable. Thanks.