I have a ward riding lawnmower Model 289707,Type 0154-01,Code 9208054e
I bought a new Muffler for it .Model 691874 And the bolts that screw into the head are just a millimeter to large, they are a 1/4 inch. What size bolts are these and where can I buy them. If I must buy a new Muffler with the bolts I will do that

Hi,
The parts beakdown lists two muffler screws. No way to tell which is which. Generally they are shoulder screws with either 1/4" or 5/16" threaded portions. The B&S part numbers are 691416 and 692198.
The IPL is at:
http://bsintek.basco.com/BriggsDocumentDisplay/Z6hrABVJ1DajI.pdf
Peace,
Clarke
PS item #675 is the screws.