Timing Belt Installation

Tools Required

• EN 46330  Timing Belt Tensioner Retaining Pin. See Special Tools .
• EN 46331  Timing Belt Tensioner Pulley Retaining Bolt. See Special Tools .
• EN 46337  Camshaft Sprocket/Crankshaft Balancer Holder. See Special Tools .

Fig 1: Aligning Crankshaft Sprocket Mark With Pointer On Oil pump Housing
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: The powertrain control module (PCM) must perform the idle learn procedure to determine the minimum throttle position and to establish idle speed when any of the following components are replaced:
• Throttle body
• Timing belt
• Timing belt drive sprocket
• Crankshaft and bearings

Refer to Idle Learn .
1. Clean the belt sprockets and covers.
2. Rotate the crankshaft and align the top dead center (TDC) mark (2) on the sprocket (237) with the pointer on the oil pump housing (1).
Fig 2: Aligning The Mark On The Sprocket With The Pointer
Courtesy of GENERAL MOTORS CORP.
3. Rotate the left camshaft sprocket to TDC by aligning the mark (2) on the sprocket with the pointer (1) on the cover.
Fig 3: Aligning The Mark On The Sprocket With The Pointer On The Rear Cover
Courtesy of GENERAL MOTORS CORP.
4. Rotate the right camshaft sprocket to TDC by aligning the mark (2) on the sprocket with the pointer (1) on the cover.
Fig 4: View Of EN 46331 On The Timing Belt Tensioner
Courtesy of GENERAL MOTORS CORP.
5. Install the EN 46331  . See Special Tools . Screw the EN 46331  all the way in by hand, until the tool contacts the timing belt tensioner. See Special Tools . Tighten until snug.
Fig 5: View Of Timing Belt
Courtesy of GENERAL MOTORS CORP.
6. Install the belt (235) onto the sprockets. Install the timing belt in a clockwise sequence starting with the tensioner pulley. Refer to Camshaft Timing Belt Alignment Diagram .
Fig 6: View Of Idler Pulley Bolt
Courtesy of GENERAL MOTORS CORP.
NOTE: Refer to Fastener Notice in Cautions and Notices.
7. Tighten the idler pulley bolt (238).

   Tighten:  Tighten the bolt to 44 N.m (33 lb ft).

Fig 7: View Of EN 46330
Courtesy of GENERAL MOTORS CORP.
8. Remove the EN 46330  . See Special Tools .
Fig 8: View Of EN 46331
Courtesy of GENERAL MOTORS CORP.
9. Remove the EN 46331  . See Special Tools .
Fig 9: View Of Guide, Balancer & Bolt
Courtesy of GENERAL MOTORS CORP.
10. Install the guide (236), balancer (228), and bolt (227). Tighten the bolt until snug.
Fig 10: Positioning The Timing Belt On The Sprockets
Courtesy of GENERAL MOTORS CORP.
11. Using the EN 46337  , rotate the crankshaft clockwise about 5 or 6 complete revolutions to position the timing belt on the sprockets. See Special Tools .
Fig 11: Aligning Crankshaft Sprocket Mark With Pointer On Oil pump Housing
Courtesy of GENERAL MOTORS CORP.
12. Align the mark (2) on the sprocket with the pointer (1) on the oil pump housing.
Fig 12: Aligning The Mark On The Sprocket With The Pointer
Courtesy of GENERAL MOTORS CORP.
13. Inspect the left camshaft sprocket for proper alignment. The TDC mark (2) on the sprocket should align with the pointer (1) on the cover.
Fig 13: Aligning The Mark On The Sprocket With The Pointer On The Rear Cover
Courtesy of GENERAL MOTORS CORP.
14. Inspect the right camshaft sprocket for proper alignment. The TDC mark (2) on the sprocket should align with the pointer (1) on the cover.
Fig 14: View Of Guide, Balancer & Bolt
Courtesy of GENERAL MOTORS CORP.
15. Remove the bolt (227), balancer (228) and guide (236).