How to repair your Avon/Leafield A7 or B7 Inflation Valve
1. Deflate the inflatable boat collar or tube and lock the inflatable valve spindle in the open position by pushing-in and twisting the valve spindle.
2. Using an A7/B7 socket/spanner or a large pair of grips (use a cloth to cover the jaws of the grips to prevent damage to the plastic valve), unscrew counter clockwise and remove the outer valve assembly from the inner assembly – grip the inner valve assembly through the inflatable collar or tube fabric to ensure that the inner assembly does not fall loose inside the tube, alternatively loop some cotton thread or string around the screw thread of
the inner valve assembly and secure the other end of the string, whilst you dismantle the valve. Whilst continuing to grip the inner valve assembly
through the inflatable tube fabric push the inner part of the valve inside the tube and carefully twist the inflation valve around so you now see the rear of the inner-valve assembly through the valve aperture in the inflatable collar or tube wall.
3. You can now unscrew the black rubber cup diaphragm from the spindle by using a pair of long nosed pliers to grip the rubber diaphragm and unscrewing it counterclockwise. Once the diaphragm has been unscrewed, the inflation valve can be turned around again, the spindle moved to the closed position and then the spindle and spring can be removed. Ensure all surfaces and valve components are clean and free from dirt or objects that could prevent the valve from sealing once re-assembled.
4. Insert the new spindle and spring into the valve, push and turn to lock the spindle in the open position and once again carefully turn the inflatable boat valve around within the inflatable collar or tube so that you can see the rear of the valve assembly, screw the new black rubber diaphragm onto the spindle, taking care not to cross thread or damage the new cup diaphragm.
5. Carefully, turn the inner valve assembly back round once again and pull the thread of the inflation valve body back through the aperture in the tube wall and screw back on the outer-valve assembly.
B7 Valve (N.b. this is the same as the A7 except contoured cap)