water in fuel

[wslade2]

have had plane away from home and hanger, so tied down outside. Some rain storms came through. Found quite a bit of water in tanks when sumping them. Open fuel doors and there is standing water in the bowl where cap is. I notice a small opening in the rear of bowl. I interpret this as a drain for collected water in the bowl. But it is not allowing water to drain out. I tried running a wire through it and got 5 inches down but still water will not drain. I put a piece of rubber tubing up to the opening and tried blowing though it but air will not pass. Am curious of the construction on back side I can not see. Is there a tube hooked up? Metal? Rubber? Is that what is blocked? I am thinking of using a compressor and trying to blow 100 psi though it but would prefer to know what is on back side before doing that. No details are given in parts or service manual. To access back side of bowl looks like would have to support wing and remove upper wing panels over fuel tanks. water pooling in the bowl where gas cap is, getting past gasket and into tank potentially dangerous. Probably removed up to about 1/2 cup of water from just one of the tanks. Any experiences with this appreciated.