I bet someone went home with a sad sack face the day that bit the drink . The fact that you even got it apart says something although until all the bits are nice and clean its hard to tell what you got . I agree with old fart ( did I just say that ) in that there s probably been some castor in the fuel . Those valves look a little ugly but they may clean up . Just be gentle , try using a scotch brite pad 1st and see what happens . NO grinders !!!