Possible Vasectomy???

I have been married to my husband for almost 3 years now and I am starting to suspect that my husband had a vasectomy before we were together. Any time I mention having children he immediatly changes the subject or says it's not going to happen for a long time so we dont need to talk about it. The thought had never crossed my mind that he could have had a vasectomy until I was talking to a friend about it a few days ago. I was told that after a man has a vasectomy his semen is clear and very runny, almost like water. Ever since I have been with my husband, his semen has been clear and very watery. Also, I noticed he has a small scar, about 2 inches long, underneath his . He denies that it is a scar, but that is what it looks like. I was just wondering if what my friend told me is true. I don't just want to come right out and ask him because I think he'll deny it even if it is true. I am curious because I want to have children in the near future.