Syntax Error (missing Operator) in query expression

Hello everyone.

This problem (or error) involves some minor SQL programming. However the coding is done in and Excel '97 enviroment and involves an Excel userform.

So, I have a syntax error that is occuring after I attempted to insert two new string items into a string variable called strVol.The two additional items are SubPort and PartialMargin.

Let me first walk you through the userform:

1. The user is requested to Add Volume -

Private Sub btnAddVolume_Click()
    Dim custName As String
'    OpportunityFrame.BackColor = DefaultColor
'    VolumeFrame.BackColor = SelectedColor
'    NotesFrame.BackColor = DefaultColor
    custName = Customer.Text & txtCustomer.Text
    If btnAddVolume.Caption <> "Cancel Volume" Then
        btnAddVolume.Caption = "Cancel Volume"
        If custName <> "" Then
            SetVolFields Show:=True
            
            lblInstruction.Caption = " Select Port, Product" & vbCrLf & "and then enter Volume and Margin, then Save"
            lblInstruction.ForeColor = vbRed
            lblInstruction.Font.Bold = True
                        
            If volCode = 0 Then
                Dim rs As New ADODB.Recordset
                rs.Open "Select Max(VolCode) + 1 as VCode from VOL", VolConn
                If rs!VCode & "" = "" Then
                    volCode = 1
                Else
                    volCode = rs!VCode
                    Set rs = Nothing
                End If
            Else
                volCode = volCode + 1
            End If
            NewVol = True
            
            Port.Text = " " ' must be a valid (existing) Port name
            SubPort.Text = " " ' must be a valid (existing) SubPort name
            Product.Text = ""
            PartialVolume.Text = ""
            PartialMargin.Text = ""
            VolSaved = 2
            VolAdded = True
            Port.SetFocus
            btnAddVolume.Caption = "Cancel Volume and Margin"
            btnSaveVolume.Visible = True
            
        Else
            MsgBox "Please select a Customer before adding a new Volume entry", vbOKOnly, "Customer is Required"
            Customer.SetFocus
        End If
    Else
        NewVol = False
        ClearVolDetails
        btnAddVolume.Caption = "Add Volume and Margin"
        btnSaveVolume.Visible = False
        VolSaved = -1
        VolAdded = False
        SetVolFields False
    End If
    volCode = 0
End Sub

A frame that was hidden on the userform then appears and the user populate the various fields namely: Port, SubPort, Product, Volume and then Margin. The user than "Saves The Volume"

Private Sub btnSaveVolume_Click()
    Dim custName As String
    Dim strVol As String
    Dim SalesOrgToUseForSave As String
    custName = Customer.Text & txtCustomer.Text
    VolSaved = -1
    If ValidateVolume Then ' validate the Volume entries
        'if Valid, then add this set of entries to the Opportunity Details grid
        SalesOrgToUseForSave = Sheets(VALIDATIONS).Range("CurrentSalesOrg")
        If Port.Text = "*ALL PORTS" Or Port.Text = "*OTHER" Then SalesOrgToUseForSave = "0000"
        If NewVol Then
            If volCode = 0 Then
                Dim rs As New ADODB.Recordset
                rs.Open "Select Max(VolCode) + 1 as VCode from VOL", VolConn
                If rs!VCode & "" = "" Then
                    volCode = 1
                Else
                    volCode = rs!VCode
                    Set rs = Nothing
                End If
            End If
            VolAdded = True
 strVol = "INSERT INTO VOL (VolCode, OpCode, Port, SubPort, Product, PartialVolume, PartialMargin, SALES_ORG) Values (" & _
                volCode & "," & lOpCode & ",'" & Replace(Port.Text, "'", "''") & ",'" & Replace(SubPort.Text, "'", "''") & "','" & Replace(Product.Text, "'", "''") & "'," & _
                PartialVolume.Text & ",'" & PartialMargin.Text & ",'" & SalesOrgToUseForSave & "')"
            addedVol.Add volCode
        Else
            VolAdded = False
            strVol = "UPDATE VOL Set Port = '" & Port.Text _
        & "', SubPort.Text" _
        & "', SALES_ORG = '" & SalesOrgToUseForSave _
        & "', Product = '" & Replace(Product.Text, "'", "''") & "'," _
        & "PartialMargin = " & PartialMargin.Text & "'," _
        & "PartialVolume = " & PartialVolume.Text _
        & " where VolCode = " & volCode
        End If
        
        VolConn.Execute strVol <-------Error
        FillOppDetails
        ClearVolDetails

        VolSaved = 1
        btnAddVolume.Visible = True
        btnAddVolume.Caption = "Add New Volume and Margin"
        btnDeleteVolume.Visible = False
        btnSaveVolume.Visible = False
        SetVolFields False
        addedVol.Add volCode
        ResetFrames
        lblInstruction.Visible = False
    End If
    volCode = 0
End Sub

Now According to the immediate window:

? strVol
INSERT INTO VOL (VolCode, OpCode, Port, SubPort, Product, PartialVolume, PartialMargin, SALES_ORG) Values (23,11,'CARIBBEAN,'AUGUSTA MF ONLY','FUEL OIL',100,'1000,'0733')

which is correct, here CARRIBEAN is an example of a Port and AGUSTA a subport and so fourth. I suspect the double and single qoutes around PartialVolume and PartialMargin are incorrect.