Austin

I got the brass body pump on a 6.2... just rebuilt one with new seals and bearings- job went well. Couple of hours later the other pump gives out! It pulled out... the pully came forward an inch or so and threw the belt off. So I'm thinking, knowing how they go together( rebuilding the other one), what keeps the pully from pulling the bearing out normally? The front seal seems to be what is expected to do this but that's not much of a retainer. I'm I missing something?? On the one that just pulled out the bearing and seals seem fine, so I'm thinking I'll just clean it up, push it back in, and epoxy the front seal back on. Any ideas/ knowledge on this out there??