sigmund,

Looking for the leak as you described seems the next step to me too.

Does your design look like this?
http://www.ponddampiping.com/asys1.html

However, If the pipe is damaged inside of the valve - draining is the only way (I know of) to make repairs. Lots of smart folks here on this board, maybe they can pitch in too.

Pictures usually help.

Gator

- Smoke 'em if you got 'em

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