How to stop a Countdown Timer?

The timer doesn't stop when I hit the trigger. I can't figure out whats wrong. Here's my script. Any ideas how I can fix this please? Thanks in advance.

 var Seconds:float=59;
 var Minutes: float = 0;
 var stopTimer : boolean;
  
 function Start() {
  stopTimer = true;     
 }

  function Update(){
  if(stopTimer){
       if(Seconds <= 0){
             Seconds = 59;

         if(Minutes >= 1){
               Minutes--; 
             }
 
             else{ 
               Minutes = 0;
               Seconds = 0;
               Application.LoadLevel("test");
               GameObject.Find("TimerText").guiText.text = Minutes.ToString("f0") + ":0" + Seconds.ToString("f0");}    
         } 
       else{
         Seconds -= Time.deltaTime;
       }
  }

 
  if(Mathf.Round(Seconds) <= 9) {
         GameObject.Find("TimerText").guiText.text = Minutes.ToString("f0") + ":0" + Seconds.ToString("f0");
 } else {
         GameObject.Find("TimerText").guiText.text = Minutes.ToString("f0") + ":" + Seconds.ToString("f0");
 }}

     function OnTriggerEnter(hit : Collider){
     if(hit.gameObject.tag == "Finish"){
         stopTimer = false;
 }}