Small Engines (Lawn Mowers, etc.): 25 hp ohv briggs&Stratton Motor, briggs stratton, ansewer

Question
 Hi Robert! I have a 25 hp ohv I/C intek turbo cool Briggs & Stratton motor model#445777 type#0154-E1 on a Craftsman mower. I've had to replace the push rods a few times because they keep bending when the valve stem guide pushs up and won't let the valve open. I was told the valves being out of adjustment is what causes this, but I don't know and can't fined the amount of gap there supose to have(exaust and intake)can you tell me please. I have torn this engine completely apart looking for anything that could be causing the motor to run as if its out of time. I have checked everything, so if you have any ideal what could be causing this issue other than the gap setting on the valves, I would appriciate your ansewer. Thank you very much.

Answer
Hi David
According to my book, the valve specs are: Intake .007-.009  Exhaust .017-.019. One thing that can throw off the timing is the flywheel key being distorted or sheared. If you have the engine torn down, make sure the timing marks on the cam and crankshaft are aligned. Hope this helps.