I recently installed a new lift pump. There were some confusing things that happened, and I eventually figured out what was going on, and thought I'd share.

When I had the new pump sitting on the bench, it made good suction when I covered the intake port with a finger and pumped it manually. However, when I put the pump on the engine, and pumped it in an effort to prime the system, I couldn't get anything. I took it off again, and put it on again, all with the same results.

What I eventually figured out was that as I was intalling the pump, the cam in the engine which actuates the pump arm (which sticks into the crank-case) was forcing the arm up, and that rendered the external manual pump lever useless. Once I realized what was going on, I rotated the engine about a half-turn with a wrench on the fan-nut, and all of a sudden there was suction.

I primed the filter, started the engine, bled the injector lines, and then... good as new.

Hope that helps somebody.

CR

 

sounds like a lift pump is just like a machanical pump on a gasser...I know it will help me when I ahve to change one.

 

Yep, looks very similar to a carb'd gasser fuel pump, with the addition of a priming lever (at least on the 1st Gen - haven't looked at a 2nd Gen or overvalved one).

I swapped mine out last year, and fought it from up top and underneath. When I was checking the front brakes recently it dawned on me how easy it would have been to access through the fenderwell....