A Chevy small-block fuel pump is driven by a push rod that rides an eccentric on the camshaft. This eccentric causes the up and down movement of the push rod. The bottom of the push rod rests on a shaft that extends from the fuel pump. The rod pushes down on the shaft, and spring pressure in the pump causes the shaft to lift. It works much like an old-time well pump, where the handle is cranked up and down to get water. Mechanical fuel pumps on small-block Chevys have not changed for many years with the possible exception of a return line.
Remove and cap the fuel lines with a bolt so they do not continue to leak. There should be three lines. One is the fuel supply line. The second is the fuel return line, which returns the excess fuel to the fuel tank. The last line is to the carburetor. If the lines are metal, then cap them with either rubber caps or with short pieces of hose with a bolt stuck in the other end of the rubber hose.
Remove the two bolts holding the fuel pump to the block. Take the fuel pump out by pulling it straight off.
Unfastened the smaller bolts holding the restrictor plate to the block. This is the mounting surface for the pump that keeps the fuel pump rod from coming out. Remove the plate then the fuel pump rod.
Install the new gaskets with RTV (silicone gasket maker) behind the restrictor plate and the fuel pump. Install the rod and fuel pump (in the reverse order or removal). When the fuel pump rod is back, cover it with some thick grease to hold it up in place to install the fuel pump shaft.
