How do you change Astra cambelt?

To change the cambelt on an Astra, first, ensure the engine is cool and disconnect the battery. Remove any components obstructing access to the cambelt cover, such as the drive belts and timing cover. Align the timing marks on the crankshaft and camshaft, then carefully remove the old cambelt while ensuring the timing remains in place. Install the new cambelt, making sure it's tensioned correctly, and reassemble all removed components before reconnecting the battery and starting the engine.