Useful Gates Technical Information for Cambelt Timing on the Z20LEx 2.0 Turbo family of engines; Z20LET, Z20LEL, Z20LER and Z20LEH (Astra H VXR). This is not a ‘How To’ guide but additional technical information for those with enough mechanical competency to carry out a cam belt change.
Cambelt Change Cycle suggested by the manufacturer:
Z20LET :: 4 years* or 40,000 Miles*
Z20LEL :: 8 years* or 80,000 Miles*
Z20LER :: 8 years* or 80,000 Miles*
Z20LEH :: 8 years* or 80,000 Miles*
*Whichever occurs first.
Notes: The cambelt (timing belt), plastic inlet roller and tensioner are common between all the engines (i.e. the same parts). The only different is that the LEL/LER and LEH kits use a metal exhaust roller (LET uses a plastic exhaust roller). For this reason we suggest a 6 years* or 60,000 Miles* change cycle as best practice. Always use a new tensioner retaining bolt (torx head) with the LEL/LER/LEH engines.
What is Needed……
A good toolkit with a good selection of sockets, allen head sockets, male torx sockets, a 15mm spanner (or similar) to release tension on the auxiliary drive belt and a 17mm ½” drive socket and ratchet (makes turning the engine over to check tension much easier). For the later engines a very high quality T40 Male Torx ⅜” drive socket, and a ¼” drive E10 female torx socket (a slim one) is useful for removing the timing belt cover bolt next to the tensioner once the tensioner is in the ‘rest’ position.
Do not forget a suitable Camshaft Locking Tool (widely available).
On the later engines the cambelt tensioner retaining bolt has a very shallow torx head and if you are not careful the socket can slip and/or chew out the head of the bolt. We suggest akways replacing this bolt when fitting a new belt kit (often the kits are not supplied with the tensioner bolt!)
Remember the tensioner is tensioned ANTI-Clockwise!! We see far too many incorrectly tensioned cambelts.
Torque Settings (for reference):
Toothed belt tension roller to oil pump: 20Nm
Toothed belt guide roller to cylinder block (exhaust side): 25Nm
Toothed belt guide roller to cylinder block (inlet side): 25Nm
Toothed belt cover – upper part to rear toothed belt cover: 6Nm
Toothed belt cover – lower part to rear toothed belt cover: 6Nm
When changing the cam belt always check the water pump and replace if in any doubt, especially on later engines where the change cycle of the cam belt is longer.
Gates Technical Bulletin on how to time up the engine (for reference only):
PDF Timing Information
Note: You will need a PDF reader to read this file.
Timing Belt Diagram Z20LEx
Note: E&OE. The above Technical Guidelines are provided for information only. We accept no responsibility for any loss (consequential or otherwise), damage, injury howsoever caused relating to persons undertaking their own repairs. If unsure please seek the services of a professional.