Small Engines (Lawn Mowers, etc.): 18.5 HP Briggs And Stratton problems, briggs and stratton, hp briggs

Question
Hi Eric: I have a saga here. 2 weeks ago we blew up our engine. The inside of it was in little pieces. We decided to buy a short block and put all of the parts from the old engine on the new short block.After putting everything on and torquing everything to the B&S specs we cannot get it to run. We can have it sputter sometimes and occasionally we have had it give a loud bang and shoot a flame out of the muffler. From what we can see we have put everything on correctly and have set the valve clearances as directed by the B&S website. The engine model number is a 31Q777. It almost seems like the timing might be off but that is a factory set thing from what we know. Could it be the carburateor is not set correctly and if so how do I go about setting it. Also do you know of a good source to see images of the carburator.

Answer
The Briggs illustrated parts list available from the Briggs site gives a picture of the carb.

Did the valves need adjusting?  Usually most shortblocks arrive with correct valve gaps.

Have your remove the flywheel nut and checked the flywheel key?  Did you adjust the governor according to the directions that came with the short block?

Let me know.
Eric