Test is simple gently pull the arm up to put slightly extra pressure on the valve plunger. If water stops it could be adjustment wiil stop it. If not the valve washer is worn and needs replacing.
If you don't know how to go about it email me.
robertwhiting76@hotmail.com
retired jobbing builder.
Oh! let me know if you do email what type it is either plastic or the old brass inlet valve and brass arm.
Nobby
February 2009
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