|
|
12 ENGINE 2 FAULT DIAGNOSIS ENGINE NOISES Excessive or obtrusive noise from the engine A. The exhaust system, which makes an B. External components emit the greatest variety of C. Engine internal mechanical noises which can Engine internal mechanical noises. Single or multiple, light tapping noise, particularly See Description and operation, Description 1. Is engine oil level correct? NO - Top up to correct level. See LUBRICANTS, FLUIDS AND YES - Continue. 2. Is the lubricating pressure correct? NO - See Engine Oil Pressure Test YES - Suspect valve operating mechanism. 3. To confirm diagnosis, remove the rocker covers and with the engine idling, insert a feeler gauge See Repair, Rocker Shaft Renew Heavy knocking noise (particularly on load and See Description and operation, Description 1. Is engine oil level correct? NO - Top up to correct level. See LUBRICANTS, FLUIDS AND YES - Continue. 2. Is the lubricating pressure correct? NO - See Engine Oil Pressure Test YES - Drain engine oil and filter, and examine for metallic contamination. 3. Is the oil contaminated with metal particles? YES - Suspect faulty big end bearings. To confirm diagnosis, short out the ignition to 4. If noise is not conclusively diagnosed, check the security of the flywheel and crankshaft front Heavy rumbling noise (particularly during hard See Description and operation, Description 1. Is engine oil level correct? NO - Top up to correct level. See LUBRICANTS, FLUIDS AND YES - Continue. 2. Is the lubricating pressure correct? NO - See Engine Oil Pressure Test YES - Drain engine oil and filter, and examine for metallic contamination. 3. Is the oil contaminated with metal particles? YES - Suspect faulty main bearings. If noise is not conclusively diagnosed, check the |