Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 07-26-07, 01:48 PM   #1
barba
Senior Member
Thread Starter
 
barba's Avatar
 
Join Date: Nov 2005
Bikes:
Posts: 4,083
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Problem with my Silical floor pump

This is not exactly about fixing a bike, but here goes:

My Silica Superpista is not longer inflating tires. When you push down on the handle I can tell air is being pumped out, but if I let go the handle rises (as air is pushed back out of the tire, I am guessing). My sense is that there must be a check valve somewhere that is not doing its job. Does anyone have any advice on a fix or at least what part to order? I would hate to loose this pretty pump.
barba is offline   Reply With Quote
Old 07-26-07, 02:34 PM   #2
SSP
Software for Cyclists
 
SSP's Avatar
 
Join Date: Dec 2003
Location: Redding, California
Bikes: Trek 5200, Specialized MTB
Posts: 4,618
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Try squirting a bit of oil into the small hole at the top of the pump body. It may be that the leather washer inside has gotten dried out.
SSP is offline   Reply With Quote
Old 07-26-07, 02:35 PM   #3
cny-bikeman
Mechanic/Tourist
 
Join Date: Apr 2007
Location: Syracuse, NY
Bikes: 2008 Novara Randonee - love it. Would have more bikes if I had time to ride them all. Previous bikes: 1968 Motobecane Mirage, 1972 Moto Grand Jubilee (my fav), Jackson Rake 16, 1983 C'dale ST500.
Posts: 6,322
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 54 Post(s)
If you push the inflator of the pump on too far on a presta valve the valve end will be pushed down (open) and you may experience the air pushing back out of the tube. Try not pushing the pump end on so far, or push all the way down and then pull back a bit. On a most pumps there is a check valve that could be bad. http://www.bikepro.com/products/pumps/silcfloor.shtml

Last edited by cny-bikeman; 07-26-07 at 03:02 PM.
cny-bikeman is online now   Reply With Quote
Old 07-26-07, 02:44 PM   #4
barba
Senior Member
Thread Starter
 
barba's Avatar
 
Join Date: Nov 2005
Bikes:
Posts: 4,083
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I tried putting oil down the hole & have tried several backing the chuck back in case it was holding the valve open. Neither seem to the the issue. It seems that around 50-60psi, the pressure of the tire just forces air back up the pump barrel. The pump is really fairly new, and I am starting to doubt the Silica hype a little.
barba is offline   Reply With Quote
Old 07-26-07, 02:46 PM   #5
Gonzo Bob
cycles per second
 
Gonzo Bob's Avatar
 
Join Date: Oct 2003
Location: Minnesota
Bikes: Vitus Aluminum, DiamondBack Apex, Softride Powerwing 700, "Generic" Ishiwata 022, Trek OCLV 110
Posts: 1,790
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Are you sure air is coming out of the tire? The Presta valve should be closing and not allowing this. Or do you have Schaeder valves?

If you have Presta valves and they are working, it's probably a bad check valve. But air is not coming out of the tire. It's coming from the pressure gauge/reservoir block. I 'spose a bad check valve could limit the amount of air you can get into a tire, though. I've had a Silca Pista (I think is has a bigger reservior block than the Super Pista) for 20+ years now and have never had problems with it.

Last edited by Gonzo Bob; 07-26-07 at 02:51 PM.
Gonzo Bob is offline   Reply With Quote
Old 07-26-07, 02:49 PM   #6
barba
Senior Member
Thread Starter
 
barba's Avatar
 
Join Date: Nov 2005
Bikes:
Posts: 4,083
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Gonzo Bob View Post
Are you sure air is coming out of the tire? The Presta valve should be closing and not allowing this. Or do you have Schaeder valves?

If you have Presta valves and they are working, it's probably a bad check valve. But air is not coming out of the tire. It's coming from the pressure gauge/reservoir block.
They are presta valves and in good working order (I have tried on several bikes and am experiencing the same problem). The idea that the air is coming out of the tire was just a guess. It just feels like the tire inflates a bit and as the handle magically rises when I let go, the tire deflates to where it was.
barba is offline   Reply With Quote
Old 07-26-07, 02:55 PM   #7
SSP
Software for Cyclists
 
SSP's Avatar
 
Join Date: Dec 2003
Location: Redding, California
Bikes: Trek 5200, Specialized MTB
Posts: 4,618
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Perhaps it's time to get a modern floor pump...I recommend the Joe Blow line.
SSP is offline   Reply With Quote
Old 07-26-07, 03:10 PM   #8
freako
Banned
 
Join Date: Feb 2006
Bikes:
Posts: 498
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by barba View Post
They are presta valves and in good working order (I have tried on several bikes and am experiencing the same problem). The idea that the air is coming out of the tire was just a guess. It just feels like the tire inflates a bit and as the handle magically rises when I let go, the tire deflates to where it was.
It almost seems as if the valve is not working correctly. It can't be the leather washer inside the barrel because it's actually preventing air from leaking past it and that's why the handle rises back up under pressure. SO what the hecks wrong with the valve? Hmmmmm, did you make sure you have the valve converted for use on a presta valve? You see, those pumps come with the option of allowing you to pump either Schrader or Presta, and if it's in the Schrader position it would do exactly what you described on a Presta valve. Otherwise you may have a faulty valve which is easily and cheaply replaceable.
freako is offline   Reply With Quote
Old 07-26-07, 03:14 PM   #9
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Posts: 28,917
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 94 Post(s)
There is a ball check valve in the pump base under the pressure gauge and accessable by removing the brass hex-headed fitting. Clean it and you should be ok.
HillRider is offline   Reply With Quote
Old 07-26-07, 03:28 PM   #10
barba
Senior Member
Thread Starter
 
barba's Avatar
 
Join Date: Nov 2005
Bikes:
Posts: 4,083
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by HillRider View Post
There is a ball check valve in the pump base under the pressure gauge and accessable by removing the brass hex-headed fitting. Clean it and you should be ok.
I just managed to pry open that hex head. It seems that the check valve had somehow become wedged, though there wasn't anything obviously grungy in there. That seems to have fixed it, though. Thanks for the tip. I have considered getting a Joe Blow, but when this pump is working I can get to 120PSI in a remarkably low number of strokes (and it is handsome). Thanks all.
barba is offline   Reply With Quote
Old 07-27-07, 07:53 AM   #11
tellyho
Your mom
 
Join Date: Aug 2006
Bikes:
Posts: 2,541
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Silca is better than Joe Blow cause you can take it apart, as above.
tellyho is offline   Reply With Quote
Old 07-27-07, 08:03 AM   #12
SSP
Software for Cyclists
 
SSP's Avatar
 
Join Date: Dec 2003
Location: Redding, California
Bikes: Trek 5200, Specialized MTB
Posts: 4,618
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by tellyho View Post
Silca is better than Joe Blow cause you can take it apart, as above.
I ditched my Silca a few years back.

One reason was that I cut my fingers several times on the sharp exposed ends of the wire hose clamp that secures the brass pump head to the hose (talk about an "old school" design!).

It was also fairly common for the pump head to pop off when putting air in tires.

And the final straw was the difficulties involved in switching between Presta and Schraeder modes (most modern pumps don't require disassembling the pump head to do that!).

The Silca *is* a classic, but compared to modern pumps it's a PITA (IMO, of course...YMMV).


FWIW, my 10 year old Joe Blow is used daily, and has never had to be taken apart.

Last edited by SSP; 07-27-07 at 08:15 AM.
SSP is offline   Reply With Quote
Old 07-27-07, 08:11 AM   #13
barba
Senior Member
Thread Starter
 
barba's Avatar
 
Join Date: Nov 2005
Bikes:
Posts: 4,083
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
While looking about on their page for where that check valve was hiding, I saw that they are introducing a new brass head that has a locking mechanism. I replaced the stock hose clamps long ago. The ratcheting ones sold in the plumbing isle are much better than the stock clamps.

barba is offline   Reply With Quote
Old 07-27-07, 10:38 AM   #14
GV27
Light Makes Right
 
GV27's Avatar
 
Join Date: Apr 2005
Location: Green Mountain, Colorado
Bikes: Gianni Motta Criterium, Dean Hardtail
Posts: 1,521
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
OOOOhhhhhhhh! I got get me one of those!

I guess my Silca Track Pump isn't the most convenient, but seeing as it's over 30 years old and still going strong (with a couple of rebuilds over the years) I ain't ditchin' it for nothin'!
GV27 is offline   Reply With Quote
Old 07-27-07, 10:49 AM   #15
RB1-luvr
I don't know.
 
RB1-luvr's Avatar
 
Join Date: May 2003
Location: Meriden, CT
Bikes: '90 Bridgestone RB-1 , '89 SuperGo Access Comp, 2009 Access, 2010 Windsor Touring, 2014 Ritchey Road Logic, 2009 Kestrel Evoke SRAM Rival, 2003 Trek OCLV USPS livery, 1936 Westfield Seminole, 1946 Monark, '47 Western Flyer
Posts: 1,035
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
I love my Silca. Christmas gift from my father in 1985, I'm gunna try to keep it going as long as I need it. this thread reminds me I need a new leather plunger. and ya, that locking brass head is sweeeet.
RB1-luvr is offline   Reply With Quote
Old 07-27-07, 11:21 AM   #16
idcruiserman
Mmmmm potatoes
 
idcruiserman's Avatar
 
Join Date: Sep 2006
Location: Idaho
Bikes:
Posts: 1,921
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by barba View Post
While looking about on their page for where that check valve was hiding, I saw that they are introducing a new brass head that has a locking mechanism. I replaced the stock hose clamps long ago. The ratcheting ones sold in the plumbing isle are much better than the stock clamps.
Is that a dual use head?
idcruiserman is offline   Reply With Quote
Old 07-27-07, 11:25 AM   #17
barba
Senior Member
Thread Starter
 
barba's Avatar
 
Join Date: Nov 2005
Bikes:
Posts: 4,083
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by idcruiserman View Post
Is that a dual use head?
Here is their description:
"Adaptor for Presta Valve with locking device
#1 for bladed spokes wheels and for short valves."

Edit: and I just noticed my spell check is turning "silca" into "silica". My apologies to Italians.
barba is offline   Reply With Quote
Old 07-27-07, 02:13 PM   #18
GV27
Light Makes Right
 
GV27's Avatar
 
Join Date: Apr 2005
Location: Green Mountain, Colorado
Bikes: Gianni Motta Criterium, Dean Hardtail
Posts: 1,521
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Anybody know where to get one?
GV27 is offline   Reply With Quote
Old 07-27-07, 04:21 PM   #19
stokessd
Senior Member
 
stokessd's Avatar
 
Join Date: Jun 2007
Location: Fort Wayne, Indiana
Bikes: Stowe(3), Terry(1), Cannondale Tandem (1)
Posts: 200
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I also love my silca. I just bought new washers for the chuck and a replacement leather washer and a new one of those valves that the OP needed to clean. Total cost was like $8, I only needed the chuck washer, but I wanted enough parts to keep this thing running until I die. The pump is fantastic, I've had it since my blue two barrel Zefal self destructed in the early 80's.

You guy can keep your plastic pumps, I'll keep using this columbus tubing baby until I die.

Sheldon
stokessd is offline   Reply With Quote
Old 07-27-07, 04:24 PM   #20
barba
Senior Member
Thread Starter
 
barba's Avatar
 
Join Date: Nov 2005
Bikes:
Posts: 4,083
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by GV27 View Post
Anybody know where to get one?
Nowhere I can find, but shoot me a PM if you find it.
barba is offline   Reply With Quote
Old 07-27-07, 04:34 PM   #21
SSP
Software for Cyclists
 
SSP's Avatar
 
Join Date: Dec 2003
Location: Redding, California
Bikes: Trek 5200, Specialized MTB
Posts: 4,618
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by barba View Post
Nowhere I can find, but shoot me a PM if you find it.
With the speed with which Silca introduces new technology, perhaps they're planning on making the Presta-only locking head unit available in time for their upcoming 100th anniversary (in 2017).

Last edited by SSP; 07-27-07 at 04:50 PM.
SSP is offline   Reply With Quote
Old 07-31-07, 10:24 AM   #22
RB1-luvr
I don't know.
 
RB1-luvr's Avatar
 
Join Date: May 2003
Location: Meriden, CT
Bikes: '90 Bridgestone RB-1 , '89 SuperGo Access Comp, 2009 Access, 2010 Windsor Touring, 2014 Ritchey Road Logic, 2009 Kestrel Evoke SRAM Rival, 2003 Trek OCLV USPS livery, 1936 Westfield Seminole, 1946 Monark, '47 Western Flyer
Posts: 1,035
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
anyone know where to get the white plastic threaded piece that the leather plunger sits against?

i ordered a new plunger, but i don't want to put it in because the round plastic piece is out of round and cracked. i don't think the plunger will seal if it's that way, right?
RB1-luvr is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 07:06 PM.