Turret Rotation Problems

I am trying to create a turret which rotates to face a target. The base rotates left and right, while the head rotates up and down.

I have successfuly made the base only rotate around the y axis, but the problem I am having is making the head only rotate on it's x axis - it just doesn't work right. (Shown here)

This is the code I have for the turret: using UnityEngine; using System.Collections;

 public class Turret : MonoBehaviour
 {
     public Transform target;
 
     public Transform rotateTransform;
     private Vector3 initialRotation;
 
     public Transform pivotTransform;
     private Vector3 initialPivot;
 
     public float rotateSpeed = 0.25f;
 
     void Start()
     {
         initialRotation = rotateTransform.eulerAngles;
         initialPivot = pivotTransform.eulerAngles;
     }
 
     void Update()
     {
         if (target)
         {
             RotateTowards(target.position);
         }
     }
 
     void RotateTowards(Vector3 position)
     {
         Vector3 direction = position - transform.position;
 
         if (rotateTransform)
         {
             rotateTransform.rotation = Quaternion.Lerp(rotateTransform.rotation, Quaternion.LookRotation(direction), rotateSpeed);
 
             rotateTransform.eulerAngles = new Vector3(0, rotateTransform.eulerAngles.y, 0) + initialRotation; 
         }
 **///The problem area////**
         if (pivotTransform)
         {
             pivotTransform.rotation = Quaternion.Lerp(pivotTransform.rotation, Quaternion.LookRotation(direction), rotateSpeed);
 
             pivotTransform.eulerAngles = new Vector3(pivotTransform.eulerAngles.x, 0, 0);
         }
     }
 }