Override Route Table Default Values Using Html.ActionLink?

Global.asax route values
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional, filterDate = DateTime.Now.AddDays(-1), filterLevel = "INFO" } // Parameter defaults
);

Here's my actionlink

@Html.ActionLink(item.MachineName, "Machine", new { id = item.MachineName, filterLevel = "hello" }, null)

When the filterlevel is specified in the actionlink, it generates a url like this: [URL] Which is the same page as I am currently on. If I change the actionlink to use a property other than one that has a default value in the route table (yes, if I use filterDate it messes up too), it generates a link like this:..............