CUP-BEARING 1119036 - Caterpillar

Ignition systems can cause electrical shocks. Avoid contacting the ignition system components and wiring.Do not attempt to remove the valve covers when the engine is operating. The transformers are grounded to the valve covers. Personal injury or death may result and the ignition system will be damaged if the valve covers are removed during engine operation. The engine will not operate without the valve covers.
Maintenance of the spark plugs is required in order to achieve the following benefits:
Normal fuel consumption
Normal level of emissions
Maximum service life of the spark plugsThe service life of the spark plugs is affected by fouling due to deposits from the oil and by peak voltage. Maintenance of the ignition system is also affected by voltage. Higher voltage is required by higher inlet manifold air pressure and a higher compression ratio. Higher voltage reduces the service life of components such as spark plugs, wires, and transformers.Removing the Spark Plug
Illustration 1 g00787369
(1) Bolt (2) Valve cover (3) O-ring seal
Remove bolts (1). Remove valve cover (2). Inspect O-ring seal (3). If the seal appears to be worn or damaged, discard the seal and use a new seal for assembly.
Pulling on the wiring harness may break the wires. Do not pull on the wiring harness.
Illustration 2 g00787367
(4) Wiring harness (5) Transformer (6) Lip seal (7) Spark plug
Disconnect wiring harness (4) from transformer (5). Be careful depressing the retainer clip away from the connector. Pull transformer (5) straight away from the cylinder head.
Inspect lip seal (6). If the seal is worn or damaged, discard the seal and use a new seal for assembly.
Illustration 3 g00787371
(8) O-ring seal