i have an 86 gmc and the pump is on the right side of the block and it runs off the cam. it has three ports on it. if it is mechanical then when replacing it you should slide the pump down and in, so the pushrod is resting on the pumps lever. a good trick for getting the pump in below the push rod is to use axle grease. coat the rod in a generous amount so that the grease sticks the rod in place, holding the rod up and out of the way as you install the pump. It is best to have to engine as cool as possible with this or the grease won't hold as well.
where i the fuse for a fuel pump on 1991 gmc truck
how do i install a fuel pump on 99 gmc serra 5.3 vertex
In the gas tank.
It is inside the fuel tank .
Mounted on top and inside the fuel tank.
you have to drop the gas tank, the fuel pump goes in the top of the tank.
That truck has a fuel pump inside of each tank.
in the gas tank.
through the tank
Mounted on top and inside the fuel tank.
Located inside fuel tank
GMC vehicles do not use inertia/reset switches.