Mercury 18-HP Engines Parts Catalog Search Diagrams by Model 2 HP 3 HP 4 HP 5 HP 6 HP 7 HP 8 HP 9.9 HP 10 HP 15 HP 18 HP 20 HP 25 HP 30 HP 35 HP 40 HP 45 HP 50 HP 55 HP 60 HP 65 HP 70 HP 75 HP 80 HP 85 HP 90 HP 95 HP 100 HP 110 HP 115 HP 125 HP 135 HP 140 HP 150 HP 175 HP 200 HP 220 HP 225 HP 250 HP 275 HP 300 HP 350 HP 400 HP HP/Displacement Serial Range top top 18 Hp 18 5837437 THRU 6416712 Go 6416713 THRU 6443972 Go 7173723 THRU 7207857 Go 7207858 THRU 7209532 Go 9332837X THRU 9390058X Go 9308306 THRU 9378115 Go 9378116 THRU 9415100 Go 8071973 & Up Go 18XD 6443973 THRU 0B238463 Go 7209533 THRU 0A730006 Go 9378151 THRU 9507380 Go 18 (2 CYL.) (International) 0N001590 THRU 0N055284 Go 0N055285 & Up Go