I had to replace the water pump on our Ford 4600 Tractor this Spring. I went to put the new water pump on and tested it by pouring water in the upper radiator hose and it leaked. So I took it off and put some RTV on it and put it back on and same result...leak. I returned the water pump and got a new one thinking it may be warped....no luck it still leaked. I have put that water pump on at least 20 times now with the end result being the same...leaking. Could it be that the block is warped there? The old water pump didn't leak so I wouldn't think that this would be the issue but at this point I'm open to any and all suggestions.