How to stop water continuously trickling? ?

Replace the inlet valve. The old one cannot be dismantled and cleaned out.

Lincoln Appliance NZ
May 2016

Possibly the inlet valve has either failed or has something in it preventing it from shutting off.

I don't know if these can be dismantled to clean. A new valve may be in order.

These are some threads I found in other forums that may be useful to review and keep on file somewhere.

http://www.fixya.com/support/t25744832-simpson_eziset_550_stop_filling_anyone

http://www.justanswer.com/australia-whitegoods/5dkgj-hi-simpson-washing-machine-unsure-age-bought-2nd.html

http://www.fixya.com/support/t18248934-simpson_swt802sa

Spares available here (In Australia) http://spares.bigwarehouse.com.au/index.php?cPath=64677

Anon
May 2016