Update main viewmodel when partial view updated via ajax post - asp.net-mvc

Question

I am trying to get the viewmodel on the page to update when a partial view is updated via an ajax post. The partial view updates correctly but on the next update call the model seesm to have reverted back to the orginal state.
The partial view is a table and I am either adding or deleting a row. The codde is included below any ideas as to how this can be done.
page code is
<div class="filters">
<fieldset class="source">
<legend>Search Attributes</legend>
<div id="attributes-filter">
#Html.Partial("_EditSearchQuery")
</div>
</fieldset>
</div>
<div>
<a id="addRowLink" class="add-row-link" href="#">Add new clause</a>
</div>
</div>
</div>
-- partial view is
<table id="searchClauses" class="clauses">
<tbody>
<tr class="header">
<td class="add-remove"></td>
<td class="logical">And/Or</td>
<td class="field">Field</td>
<td class="operator">Operator</td>
<td class="value">Value</td>
</tr>
#foreach (SearchClause item in Model.searchClauses)
{
<tr class="clause clause-row" id=#item.RowID>
<td class="add-remove">
<a href="#" title="Remove this filter line" id=#item.ID >Delete</a>
</td>
<td>
#Html.DropDownListFor(modelitem => item.logicalTypeValue, new SelectList(item.logicalTypeList, "Value", "Text", "Selected"), new { style = "width: 60px" })
</td>
<td>
#Html.DropDownListFor(modelitem => item.fieldListValue, new SelectList(item.fieldList, "Value", "Text", "Selected"))
</td>
<td>
#Html.DropDownListFor(modelitem => item.operatorListValue, new SelectList(item.operatorList, "Value", "Text", "Selected"), new { style = "width: 60px" })
</td>
<td>
#Html.TextBoxFor(modelitem => item.valuesList[0], new { style = "width: 130px" })
</td>
</tr>
}
</tbody>
-- script
<script type="text/javascript">
$(function () {
// Save quiz view - new or existing.
$("#attributes-filter").on("click", "a", function () { // A jQuery delegated event - #EditQuiz is always present, a.SaveQuiz only exists when the _ElearningQuiz partial view is loaded.
deleteRow($(this).attr("id"));
});
function deleteRow (id) {
var rowData = {
'id': id,
'model' : #Html.Raw(Json.Encode(Model))
};
$.ajax({
url: "/Participant/DeleteClause",
type: "POST",
data: JSON.stringify(rowData),
contentType: "application/json; charset=utf-8",
success: function (result) {
$("#attributes-filter").html(result);
},
error: function (jqXHR, textStatus, errorThrown) {
alert("Status: " + textStatus + " Error: " + errorThrown);
}
});
};
$("#addRowLink").click(function () {
var model = #Html.Raw(Json.Encode(Model))
$.ajax({
url: "/Participant/AddClause",
type: "POST",
data: JSON.stringify(model),
contentType: "application/json; charset=utf-8",
success: function (result) {
$("#attributes-filter").html(result);
},
error: function (jqXHR, textStatus, errorThrown) {
alert("Status: " + textStatus + " Error: " + errorThrown);
}
});
});
});
</script>
-- controllers
[HttpPost]
public ActionResult AddClause(DynamicSearchModel model)
{
int campaignId = SessionManager.CampaignId;
int clientId = SessionManager.ClientId;
var newClause = _participantServiceClient.NewSearchClause(campaignId, clientId, 2);
newClause.ID = model.searchClauses.Count + 1;
model.searchClauses.Add(newClause);
return PartialView("_EditSearchQuery", model);
}
[HttpPost]
public ActionResult DeleteClause(string id, DynamicSearchModel model)
{
int _id = int.Parse(id);
model.searchClauses.RemoveAt(_id - 1);
return PartialView("_EditSearchQuery", model);
}