My Caroma cistern works OK if either flush button is held down for a full-length flush. But if either button is held down for a shorter time, the outlet valve does not close and water keeps running into the bowl. Then pushing the button again immediately and holding for full flush fixes the problem. Is it likely that I can fix this? How do I disassemble the mechanism? I know how to remove the float and replace the inlet valve, but I haven't done more than that.
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