I have a Briggs 16.5 , it misfires when you speed it up, with some backfiring . This started after I replaced the starter. The flywheel was removed to remove starter, so things were moved , did I not adjust the coil right ? How do you time this unit?:confused:

Check the flywheel key

Hi,
The flywheel key would be the place to start. You do not have to remove the flywheel to replace the starter on any Briggs I know of. There are recesses in the flywheel to facilitate that.
An improperly torqued flywheel will shear the key.
Peace,
Clarke