Spark plug renewal (12 000 Mile (20 000 Km) / 12 Month Service)
1 The correct functioning of the spark plugs is vital for the correct running and efficiency of the engine. It is essential that the plugs fitted are of the type appropriate for the engine.
2 Make sure that the ignition is switched off before inspecting the HT leads to see if they carry their cylinder numbers - if not, number each lead using sticky tape or paint.
3 Where necessary, for improved access, remove the air cleaner assembly.
4 Disconnect the leads from the plugs by pulling on the connectors, not the leads.
5 Clean the area around each spark plug using a small brush, then using a plug spanner (preferably with a rubber insert), unscrew and remove the plugs. Cover each exposed spark plug hole with a clean rag to prevent the ingress of any foreign matter.
6 Before fitting new spark plugs, check that the threaded connector sleeves are tight.
7 Check the electrode gap of each plug with a feeler blade of the specified thickness and if necessary, bend the outer electrode with a proper spark plug gapping tool to set the gap to the specified clearance.
8 Coat the threads of each plug with suitable anti-seize compound, taking care not to contaminate the electrodes.
9 Screw in the spark plugs by hand, then tighten them to the specified torque. Do not exceed the torque figure.
10 Push the HT leads firmly onto the spark plugs and where necessary, refit the air cleaner assembly.