32 -- Valve noise or tapping from the cylinder head
Valve clearance incorrect. Adjust the clearances with the engine cold.
Valve spring broken or weak. Renew the spring set.
Camshaft or cylinder head worn or damaged. The camshaft lobes are the most highly stressed of all components in the engine and are subject to high wear if lubrication becomes inadequate. The bearing surfaces on the camshaft and cylinder head are also sensitive to a lack of lubrication. Lubrication failure due to blocked oilways can occur, but neglect of oil changes and of topping-up is the usual cause.
Worn camshaft drive components. A rustling noise or light tapping can be emitted, by a worn cam chain or worn sprockets and chain. If uncorrected, subsequent cam chain breakage may cause extensive damage. The worn components must be renewed before wear becomes too far advanced.
© April 2014