Short & long water pumps

[studiog]

Can anyone educate me on the difference between long and short water pumps? Is it just the lengh of the lower hose connection pipe? Thanks :confused

 

[Bob Chadwick]

I'm pretty sure it's the different lengths of the 4 "legs" on the waterpump that go against the block over the timing cover.

 

[WayneC]

It's the distance from the block to the fan mounting surface. bobchad is right about the difference (about 2 inches) being in the 4 legs. I think the long pump started on Chevy's with the 350ci engines in 1968. Long pump, of course, puts the fan 2 inches closer to hitting the radiator.

 

[wallyknoch]

Short waterpumps are used on 55`s to 70 small blocks and 65-70 big blocks. You cannot change from short to long as belt and pulley problems prohibit this.