sounds to me like the washer is stuck over the inlet. Remove the tap from the tap body if capstan type top remove the screw just below the finger capstans gently tap the capstan head off then turn off the water and undo the tap chrome cover then remove tap from the body with and adjustable wrench look inside the tap body see if part of the washer has stuck over the inlet. Replace the washer vaselene [petrolium jelly] the washer plunger so it moves easy then replace tap in body do not overtigthen when fitting the tap. Try it out before fitting the tap chrome cover jus turn tap with capstan head loose if ok refit chrome cover and capstan. Other typ is the clear plastic type with chrome disc with blue ring for cold red for hot pop out this screw cover cap and remove the small brass screw lift off the tap knob. Rest is same as above.
Bob
August 2010
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