Mercury Mariner 25HP 4-Stroke Outboard Service Manual 1997, Page 248Get this manual
Specifications Gear Ratio Gearcase Capacity Lubricant Type Forward Gear Number of Teeth Pinion Gear Number of Teeth Pinion Height Forward Gear Backlash Water Pressure Idle WOT
2.42:1 14.9 IIoz(440 mL) Quicksilver Gear Lube-Premium Blend 29 Spirall Bevel 12 Spirall Bevel 0.025 in(0.64 mm) No Adjustment -4 PSI 800 rpm 12-17 PSI 6000 rpm