Small Engines (Lawn Mowers, etc.): setting tappets on OHV, briggs and stratton, ohv engine

Question
I have a 6.75 hp Craftsman Pressure Washer.  The model # is; #580.752700.  It a Briggs and Stratton engine.  The numbers on the muffler bracket are 129602-0113-E1-040224FB.  I'm not sure what codes or specs are.   I have a manual, so I know what the setting are for the tappets.   I'm just having a problem figuring out which is the exhaust and which is the intake valve.  The manual doesn't say which is which.  A friend told me the top was the exhaust valve because it was closest to the exhaust manifold.  I went to the B&S website and they show a picture of an OHV engine and they say the intake valve is on the top and the exhaust is on the bottom.   In the picture the intake valve is closest to the exhaust manifold.  I know this is probably the dumbest question you've ever gotten, but which is which?   I set it as though the top was the exhaust at 6, the bottom at 3.  When I went to start it, it wouldn't start.  I got a loud bang out of the muffler.  I pulled the head and cleaned all the carbon off the piston and valve ends.   I just can't get it adjusted.  PLEASE I need help, I can't afford to take this to a repair shop.  I realize your help is free and I can't tell you how much I appreciate free right now.
Thank You
Sharon

Answer

engine Hello Sharon
Well I have to give you kudos for working on the engine yourself.
Usually the intake is close to the carburetor and the exhaust is close to the muffler.I have enclosed a picture of the head so you can see where they are related.

Intake Valve Clearance ( in. )     .004 / .006

Exhaust Valve Clearance ( in. )  .004 / .006