I was having some fuel line problems so I decided to do some diagnosing. In the process I took apart the petcock (which never EVER leaked) and cleaned it out. Now when I put it back together it is leaking like a sieve!!! It looks like from the back, where the diaphram is. I tightened the 4 screws as much as possible and it still leaks like crazy. I can't figure it out. Everything looks exactly like it did when I opened it. The diaphram looks intact . Any ideas?