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Bladder Replacement

BLADDER REPLACEMENT IN WEBANCOR SHAFTS

  1. Before attempting to take the shaft apart make sure that all of the air has been removed, and that the source of the leak is not the valve. Dust and Teflon sealing tape can hold open the valve seat.Tape is not recommended for sealing thread, use a sealing compound instead.
  2. If the shaft has a “Schrader type valve use the #1815 BRASS INFLATOR/DEFLATOR chuck to let ALL air out of the shaft.Remove the #1815 from the air line, using a quick disconnect.
  3. Remove the FHSC screws from the VALVE end journal. The valve end journal is normally the only journal that needs to be removed. NOTE: Use a Hex key that is in good condition, since thread locking compounds are used to secure the bolts. Failure to use good keys can lead to damaged hex sockets which will make the bolt difficult to remove. If this happens use a “SOCK-IT-OUT” before trying to drill it out. Use of a CUTTING TORCH is not recommended since the journals are made from a heat treated steel and this could destroy the heat-treating and will void the shafts warranty. Extra torque is required to break the bond, but it can be done by hand with the proper key. If all else fails use a heat source to warm the bolts to break the bond of the thread locker. Do this with caution, do not overheat and damage the heat treatment of the journals.
  4. Use a slide hammer to remove the journal from the body. NOTE: End valve shafts usually would use a 1/2″ pipe thread, while a side valve would have either a 3/8″ NC or 1/2″ NC thread depending on the journal size. If a slide hammer is not available, use a 3/8″ or 1/2″ threaded rod and a sliding weight. For 1/2″ pipe thread use a 1/2″ pipe with threaded ends and a sliding weight. Slide hammer kits are available from WEBANCOR.
  5. The bladder will come out with the journal and since the lugs in a WEBANCOR SHAFT are supported by the sleeve, they do not have to be pinned up unless the lugs are to be replaced. The WEBANCOR lug shaft does not have retractor springs so broken springs parts will not be found. NOTE: ALUMINUM SHAFTS MFG. PRIOR TO MAY 1991 WITH 1/2″ WALL– WILL HAVE LUGS PINNED UP TO STOP THEM FROM FALLING IN WHEN BLADDER IS REMOVED. THIS SHAFT DOES NOT HAVE A SLEEVE. (THIS SHAFT CAN BE UPDATED WITH A NEW BLADDER, END CAPS AND SLEEVE.)
  6. Pull/twist the bladder out of the journal socket. The bladder uses an “O RING” fitting so that the bladder comes out easily.
  7. Measure the length of bladder and cut a new piece to size. DO NOT USE A BLADDER THAT IS TOO SHORT. THE BLADDER END CAPS MUST FIT INSIDE THE JOURNAL SOCKET. FAILURE TO DO THIS WILL ALLOW THE BLADDER NO PROTECTION AND CAN FAIL PREMATURELY. Trim the outer edge of the bladder at about 45 degrees to aid insertion into the end cap. Push the center part of the end cap well into the bladder about 1/2″ below the end, it will be a snug fit so this part will not fall further in. Push on the outer cap until it can be assured that the bladder end is inserted as far as it will go. Using a long 1/2-13 bolt threaded into the end cap center, pull the center into the outer cap. Change bolt for proper end cap bolt, with O’ring and washer as per diagram, and tighten until seated. Repeat for both ends. Check completed length against shaft body tube, it is better to be slightly long than too short. We also suggest that fiberglass reinforced tape be wrapped around the bladder at the end cap to reduce the chance of the end cap cutting into the bladder.
  8. Replace the “O rings”(#012). If you do not have the proper replacement use a 90 Duro. #012 ring. This is very important since the 70 Duro. are easily damaged. Lubricate the O’rings with white or silicone grease to prevent damage while being installed into the journal socket. Replacing the journal is the opposite of removal. Make sure that the fit between the journal and the tube is tight. If the fit is loose, the bolts will break. Never use a shaft with any broken bolts, it will allow the journal to flex in the body making the fit looser to the point that bolts will continue to break. If this happens return the shaft to WEBANCOR for a rebuild to make it safe. Use new flat head socket cap screws of the correct length, incorrect lengths can damage the bladder end caps. It is important to use a non permanent thread locking compound on the bolts. Use a thread compound on the valve threads not tape, tape tends to “string” and gets into the valve seat, allowing it to leak

Do not test inflate a shaft without making sure the bolts are tight, a high speed “rocket” could be the result.

It is usually a good idea to inflate a shaft with a #1641 valve to 90 psi and check with a pressure gauge periodically for loss of pressure. The pressure will drop slightly each time a pressure test is done, this is normal and should be taken into account. This pressure test cannot be done with push button valves. Make sure that the valve threads are sealed with thread compound.