Originally Posted by lewtot184
Originally Posted by poboyengineering
I was going to post this same question about the sponge.
Since not all pumps have it, is there a downside or advantage to leaving it out?
all carter 3 valve pumps i've messed with have the sponge. i take my pumps apart and re-work them and don't put the sponge back in with no adverse effects. i say keep it if you want, remove it if you don't; hasn't made any issues one way or the other for me.


If you are dealing with original fp from the 60s and early 70s you won't see that foam. Later version and the 6903/4862 you will, but not always.

Last edited by dragon slayer; 10/25/21 09:56 AM.