On Sep 10, 6:29 am, meb <[email hidden]>
Quoted message said:I've got a Wrench Floor Pump with a dual presta-shrader pair of holes on
the head and a valve internal to the head that switches between holes.
I thought the valve was controled by whichever hole had something to
clamp on. The pump sometimes fails to switch to the correct hole-I
thought it was a case of intermittent failure. Yesterday, I noticed
the pump switches to shrader if I hold the holes facing up when
unpressurized, presta if the holes are facing down-although it
sometimes needs a tap to get the valve to switch over. Once
pressurized, it seems to lock into whatever valve type was started from
depressurized.
Is this the way this pump is supposed to work, or have I got some funky
intermittent failure going on here?
If this is a common malfunction, is there a remedy?
--
meb
I've noticed the same on my Wrench Force pump head and the same head
I've seen on other pumps. I took mine apart (just prerssed out the
aluminum pivot shaft) and found there's a ball valve between the two
holes: it falls away from (and blocks) whichever hole you're not
using. Kind of clever really. But like yours, mine didn't block the
right hole sometimes. I added a bit of TriFlow (there's probably a
better lube for plastics out there) to help it move more freely,
thinking it might be sticking if it dried out a bit, and it seemed to
work a little better.
Otherwise I like that pump head because I can switch the Presta and
Schraeder rubbers and use the head "as is" to pump disc wheels and tri
spokes (no "crack pipe" adapter needed).
I'm pretty sure you can get a replacement head from Trek dealers
(might be part of a replacement hose?). Maybe it's under warranty?
