You may have picked up some sort of trash in your fuel hose. It happened to me one time with an OS.91. The trash will either be at the inflight needle or inside the nipple at the carburetor.

You can flush it out of your fuel hose by disconnecting your fuel hose from your tank (or tanks) and then back flush your fuel hose (or hoses) from where it attaches to your carburetor. Try to catch the fuel in a glass jar so you can see what comes out. You may have to disassemble your carb to get any trash that may have found it's way into it.