ASP.NET MVC4 AJAX.BeginForm AjaxOptions OnSuccess not called

public class CarsController : Controller
{
    private ExpDb db = new ExpDb();

    //
    // GET: /Cars/

    public ActionResult Index()
    {
        return View(db.Cars.ToList());
    }



    //
    // GET: /Cars/Edit/5

    public ActionResult Edit(int id = 0)
    {
        CarModel carmodel = db.Cars.Find(id);
        if (carmodel == null)
        {
            return HttpNotFound();
        }
        return PartialView(carmodel);
    }

    //
    // POST: /Cars/Edit/5

    [HttpPost]
    public JsonResult  Edit(CarModel carmodel)
    {
        if (ModelState.IsValid)
        {

            db.Entry(carmodel).State = EntityState.Modified;
            db.SaveChanges();
            //return RedirectToAction("Index");
             return Json(JsonResponseFactory.SuccessResponse(carmodel),JsonRequestBehavior.DenyGet);
        }
      else {
            return Json(JsonResponseFactory.ErrorResponse("Please review your form"), JsonRequestBehavior.DenyGet);
        }
    }

    @model IEnumerable<AjaxSamples.Models.CarModel>

@{
ViewBag.Title = "Index";
}
<div id="commonMessage"></div>
<p>
@Html.ActionLink("Create New", "Create")
</p>
<table>
<tr>
    <th>
        @Html.DisplayNameFor(model => model.ImageFileName)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.Name)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.Description)
    </th>
    <th></th>
</tr>

@foreach (var item in Model) {
<tr>
    <td>
        @Html.DisplayFor(modelItem => item.ImageFileName)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.Name)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.Description)
    </td>
    <td>
        @Html.ActionLink("Edit", "Edit", new { id = item.Id }, new { @class = "editLink" }) |
        @Html.ActionLink("Details", "Details", new { id=item.Id }) |
        @Html.ActionLink("Delete", "Delete", new { id=item.Id })

        <button id="opener">Open Dialog</button>
    </td>
  </tr>



 }

</table>

 <div id="updateDialog" title="Update Car"></div>
 <script type="text/javascript">
 var linkObj;
 $(function () {
    $(".editLink").button();

    $('#updateDialog').dialog({
        autoOpen: false,
        width: 400,
        resizable: false,
        modal: true,
        buttons: {
            "Update": function () {
                $("#update-message").html(''); //make sure there is nothing on the message before we continue                         
                $("#updateCarForm").submit();
            },
            "Cancel": function () {
                alert('sd');
                $(this).dialog("close");
            }
        }
    });

    $(".editLink").click(function () {
        //change the title of the dialog
        linkObj = $(this);
        var dialogDiv = $('#updateDialog');
        var viewUrl = linkObj.attr('href');
        $.get(viewUrl, function (data) {
            alert(data);
            dialogDiv.html(data);
            //validation
            var $form = $("#updateCarForm");
            // Unbind existing validation
            $form.unbind();
            $form.data("validator", null);
            // Check document for changes
            $.validator.unobtrusive.parse(document);
            // Re add validation with changes
            $form.validate($form.data("unobtrusiveValidation").options);
            //open dialog
            dialogDiv.dialog('open');
        });
        return false;
    });

});
function err(data) {
    alert(data);
}


 function updateSuccess(data) {
    alert(data);
}

@model AjaxSamples.Models.CarModel

@{
ViewBag.Title = "Edit";
}

@using (Ajax.BeginForm("Edit", "Cars", new AjaxOptions
    {
        InsertionMode = InsertionMode.Replace, 
        HttpMethod = "POST",
        OnSuccess = "updateSuccess"
    }, new { @id = "updateCarForm" }))
 {
 @Html.ValidationSummary(true)
<div id="update-message" class="error invisible"></div>
<fieldset>
    <legend>CarModel</legend>

    @Html.HiddenFor(model => model.Id)

    <div class="editor-label">
        @Html.LabelFor(model => model.ImageFileName)
    </div>
    <div class="editor-field">
        @Html.EditorFor(model => model.ImageFileName)
        @Html.ValidationMessageFor(model => model.ImageFileName)
    </div>

    <div class="editor-label">
        @Html.LabelFor(model => model.Name)
    </div>
    <div class="editor-field">
        @Html.EditorFor(model => model.Name)
        @Html.ValidationMessageFor(model => model.Name)
    </div>

    <div class="editor-label">
        @Html.LabelFor(model => model.Description)
    </div>
    <div class="editor-field">
        @Html.EditorFor(model => model.Description)
        @Html.ValidationMessageFor(model => model.Description)
    </div>

    <p>
        <input type="submit" value="Save" />
    </p>
</fieldset>
}

<div>
@Html.ActionLink("Back to List", "Index")
</div>