Mercury Mariner Outboard 225 3 Litre Service Manual 1994, Page 94Get this manual
Fuel System(Continued)
a Enrichment Hose Fitting
bCarburetor NumberFuel Mixture Adjustment ScrewOff IdleProgression" Ajr Jet (2)Back Draft Vent Jet (Ol'le, if equipped)
fIdle Air Jet (one)High Speed Fuel Jet Access Plug (2)