I just bought a maintenance/repair kit for my old Zefal Plus floor
pump. That's the old style Zefal, two barrels, blue, it's dated 1989
or thereabouts. I think it may have been called 'Double Shot' at one
point. The maintenance kit includes all new o-rings, new seals, new
piston caps (or whatever they're called). I even got a new hose for
it.
I reassembled the thing and now it won't pump on the downstroke but it
pumps well on the upstroke. Also, after being connected to the tire,
air goes from the tire to the pump and sort of sucks the pistons back
in, making it almost impossible to pull.
All in all in interesting problem. I've called ZEFAL at 888-515-7867
and said that maybe I may have a defective check valve (I've read
about it on the newsgroups) and asked them where is this valve. They
didn't know (!). I've read that it's in the black base somewhere, but
all I find are two plastic allen screws that when removed, sort of
look like valve stems or something, but no spring, no little ball, no
nothing.
That pump is/was great, best pump I've ever owned. I've emailed ZEFAL
asking about that check valve, and while I'm waiting for an answer
from them I thought I'd ask here to see if anyone has some insight.
Thanks.