Ford Repair: 88 ford festiva., worn piston rings, ford festiva

Question
the valvbe cover keeps sending oil back in to the air filter housing on the carburator when it overheats. I do most work myself but i can't seem to diagnose this. any help?

Answer
The engine oil coming up into your air filter housing is called "blow-by".  It is usually the result of too much pressure in the crankcase, it could be caused by a stuck PCV Valve, a clogged breather element, or worn piston rings.  Try not to let your engine overheat.  Other than low and/or dirty oil in the engine, overheating is the next-most harmful.  

I hope this helps,
Dave