Reply To: Carb kits for Merc 7.5 #7106835

[David Stanton]

My 2004 Sierra catalog shows the 18-7215 kit used only in the 1980 and up 4 cylinder 45 and 50 HP….but like you said, the parts all look right for the carb and its fuel pump. The 45 and 50 HP 4 cyls use multiple carbs, so maybe it’s a similar carb.

It shows 18-7013 for 1969-1973 7.5 HP, and for 1972-1985 7.5s it shows no carb kit, but a 18-7007 carb gasket kit. The gaskets in the 18-7007 look the same but there are more small washer-type gaskets in the 7007 and two sizes of carb to manifold gasket.

18-7057 is a needle and seat for 1969-1972
18-7295 is a needle and seat for 1972-1985, but that is the needle with the spring on one end that was incorrect and didn’t work in the 1975 I rebuilt.

I often find conflicting use listings for Sierra Mercury parts.

Oh – and you asked how the fuel pump gets its pulses. There is a small hole, about 1/8 inch diameter, in the carb to manifold gasket that lets manifold pulses route through a passage in the carb to the fuel pump.
Dave