Carburetor Rebuild: Mercury Black Max


From 1976 to 1997 the carbureted Mercury Black Max outboards, including most all 2.0, 2.4, or 2.5 Liters models between 135, 150, 175, 200, 225, and 245 hp motors, came with either WH, WHM, or WMV series carbs. Rebuilding these carbs is fairly straight forward and kits are available for all. The basic carburetor rebuild kits part numbers are as follows:

The WH Carb Gasket Kit from Sierra is part #: 18-7005 or Mercury OEM part #: 1395-6452. If needed, the Needle & Seat from Sierra is part #: 18-7233 or Mercury OEM part #: 1395-7824. The complete Sierra WH Carb Kit is part#: 18-7354.

The WHM Carb Gasket Kit from Sierra is part #: 18-7213 or Mercury OEM part #: 810749-2. This kit is also with Needle & Seat.

The WMV Carb Gasket Kit from Sierra #: 18-7214 or Mercury OEM part #: 810749-3. This kit is also with Needle & Seat.

The three different kits are pictured below:

WH Carb Gasket Kit
WHM Carb Gasket Kit
WMV Carb Gasket Kit
007's picture

Turned a set of WH-7's into 22's in the process.

007's picture

Q: Just wondering what the proper float height should be on the WH carbs when they are inverted?
A: they should hang down about 1/16 of an inch

Q: I have had two needles come unseated (someone else did my rebuild) and was wondering what I can do to keep them seated.
A: Check the float height and make sure the float is closing the needle. If that does not work I would check the needle and seat for an obstruction or replace and worn/broken parts.