G'day again,
After a bit of thought about this issue, that 'black nozzle' restrictor should slow down the valve stem movement in both directions [opening and closing], providing the diaphragm is sealing properly, on both the valve stem and the edge of the diaphragm chamber.
Cheers,
Gadge
"ODK Mods can explain it to you, but they can't understand it for you..."
"Crazy can be medicated, ignorance can be educated - but there is no cure for stupid..."
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