I'm working on the same problem - for me it's when the water reservoir doesn't seal consistently in the socket at the backwall of the reservoir chamber. If you push it in firmly it's fine...if you back it off slightly, it leaks. Reservoir has been replaced so that didn't fix it - going to try to add a thin gasket tape to the nipple of the water reservoir to ensure a better seal...we'll see...
Sully
November 2010
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