Small Engines (Lawn Mowers, etc.): 25hp ohv briggs & stratton, briggs stratton, marvel mystery oil

Question
 Hi Ben! I have a 25hp ohv intek turbo cool twin cylinder Briggs & Stratton Motor model#445777 type#0154-E1. I have checked everything on this motor tring to figure out why The valve stem guide is pushing out causing push rods to bend. Is there somthing electrical that can go bad that causes motor to fire out of time and run rough and cause the above issue with the push rods. I have tore the motor down completely to check everything.

Answer
David
I am guessing that it is a 31 series. IF so, the aluminum push rod is on the Intake Valve and the steel one is on the Exhaust Valve.

Hard starting, hard to turn past compression, is typical of OHV B&S engines needing the valves adjusted.

As for the push rod, IF it isn't worn badly, which it shouldn't be in that period of time, then you may have a valve sticking OR a valve guide coming out part way hitting the valve keeper. IF you think a valve is sticking, you might try running some Marvel Mystery Oil in your fuel and won't hurt engine oil either. Use according to directions on the can.