To clean the air that is to be mixed with fuel in the carburetor.dirty air can cause cylinder to score, the rings will wear causing loss of compression,and oil. this will lead to loss in performance.
A car
The air filter assembly is usually attached to it.
Most lawn mowers are air cooled, and do not HAVE a radiator (so no antifreeze). If you have a mower with a radiator, you will need to check with the manufacturer to see what they recommend.
.010 to .012"
Remove the air filter caseing disconenct the fuel pipe remove the bolts which hold the carb in place. L Davidson lawn mower tech
The air filter is usually located inside the canister that is bolted to the carburetor.
under a plastic cover, next to the carb,
Directly into the carburetor throat (remove air cleaner).
Most likely revving due to a dirty/clogged air filter.
If you are referring to a riding lawn mower, the manual specifies 12 - 14 psi in each tire.
If you have fuel coming out of your air filter, then your carburetor bowl float is most likely gummed up an stuck. try tapping on the bowl, or you my need to take it off an clean it and the needle jet. How do you adjust air/fuel mix on a lawn mower motor?
clean the air filter air is being restricted