I have a briggs & stratton mod.#311777 type 8137E1. When the engine starts it blows oil from the crank case through the vacuum hose into the carburator. Would this be the rubber valve that's not closing properly? It doesn't seem to be stuck and is stil pliable. Please give me your opinion on diagnosing the problem.
First I would check to make sure that there is the proper amount of oil in the crankcase, and not overfilled, or smells like gas, which would indicate a leaking carb problem. the other thing I would consider would be a blown head gasket.
