LR3/Disco 3
A key locates the two drive sprockets on the crankshaft. The crankshaft's torsional vibration damper retains the sprockets
in position. The variable valve timing units and the exhaust camshaft sprockets are non-interference, non-keyed fits on
their respective camshafts; the drive being transmitted by the face to face friction load produced by the valve timing
unit/sprocket securing bolt.
Each chain has a hydraulic tensioner operated by engine oil. The primary chains are lubricated via oil squirt tubes located
at the front of the engine block, near the crankshaft drive sprockets. A jet of oil from the end of each secondary chain
tensioner lubricates the secondary chains. The primary chain tensioners act on pivoting flexible tensioner blades. The
secondary chain tensioners act directly on the chains. Guide rails are installed on the drive side of the primary chains.
Timing Cover
The aluminium alloy timing cover accommodates the crankshaft front oil seal (a PTFE lip seal). Silicon rubber in-groove
gaskets seal the joint between the timing cover and the front face of the engine.
CYLINDER HEAD COMPONENTS
