Warthog Posted January 15, 2010 Share Posted January 15, 2010 Hi, Fired up the engine of a 300Tdi Disco today and there is a significant heavy knocking coming from the engine at idle. The knocking at around the 1500 became considerably less. Theres no significant smoke on start up, or if driven upto 50mph. The oil light doesnt stay on either (oil pressure issue?) The knock does not disappear when up to temperature when at idle. The engine hasnt been run for a good year. The oil and coolant levels are fine. Im assuming big-end bearing problem, as the worst case scenerio. Where and what should i start checking before the looking at the the big-end bearings? Cheers Quote Link to comment Share on other sites More sharing options...
Turbocharger Posted January 15, 2010 Share Posted January 15, 2010 Flywheel loose, or the auto flex plate's broken? Does it change when you use the clutch (manual) or select a gear / neutral (auto)? Only speed related? Have you used a screwdriver as a stethoscope to 'see' whereabouts it's coming from? Quote Link to comment Share on other sites More sharing options...
Warthog Posted January 16, 2010 Author Share Posted January 16, 2010 Flywheel loose, or the auto flex plate's broken? Does it change when you use the clutch (manual) or select a gear / neutral (auto)? Only speed related? Have you used a screwdriver as a stethoscope to 'see' whereabouts it's coming from? Will check the Clutch comparison tommorow.Pretty sure it didnt make a differance though. The knock is more noticable from the exhaust manifold side of the engine, if that helps? Cheers Quote Link to comment Share on other sites More sharing options...
Tetsu0san Posted January 16, 2010 Share Posted January 16, 2010 Check your clearances on your valves. I had the same sort of noise and it turned out to be a broken rocker shaft which was caused by a loose bolt which holds it in place. This caused the valve clearances to be way out and caused a noise which sounded like a big end problem. It was pushing compression back into the air system which caused the noise to be more evident on the exhaust manifold side. Worth a shot? Quote Link to comment Share on other sites More sharing options...
Warthog Posted January 16, 2010 Author Share Posted January 16, 2010 Check your clearances on your valves. I had the same sort of noise and it turned out to be a broken rocker shaft which was caused by a loose bolt which holds it in place. This caused the valve clearances to be way out and caused a noise which sounded like a big end problem. It was pushing compression back into the air system which caused the noise to be more evident on the exhaust manifold side. Worth a shot? Read your post in the Discovery section of his Forum. I shall have a look today. Cheers Quote Link to comment Share on other sites More sharing options...
rusty_wingnut Posted January 16, 2010 Share Posted January 16, 2010 also worth pulling cam followers out and looking for general wear in the valve gear Quote Link to comment Share on other sites More sharing options...
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