foreigneRS

PART A - Engine, Engine Management and Turbocharger

1.1 Engine Components Front Belt Drive

1 = Camshaft sprocket gear
2 = Timing belt
3 = Tensioner - timing belt
4 = Water pump
5 = Sprocket gear - auxiliary shaft
6 = Three belt pulley
7 = V-belt - power steering pump
8 = V-belt - alternator and water pump

The overhead camshafts and the auxiliary shaft are driven by a toothed timing belt directly from the crankshaft sprocket gear. The timing belt must be replaced in service every 80.000 km (50.000 miles).

• The sprockets for the camshafts and the auxiliary shaft are located by keys.
In contrast to the standard OHC-engine the Cosworth engine has a TOC marking on the sprocket gear for the auxiliary drive.
• The eccentric type belt tensioner allows a very precise setting of the timing belt tension.

The fan belt pulley on the crankshaft drives three belts, a matched pair for the alternator and the water pump and a single belt for the power steering pump.

Tensioning of the "V" belts for the alternator and the water pump is done on the bracket for the alternator. The procedure is similar to the one for the standard OHC-engine. Tension of the "V" belt for the power steering pump is achieved by tilting the power steering pump.

There are 4 teeth on the "V" belt pulley nearest to the engine. These teeth are separated by exactly 90°. They initiate the pulses for the speed sensor (see "Engine Management").

The tooth next to the ignition timing . mark identifies the TOC position of piston NO.1. This position is reached when the flank of the tooth aligns with the marking on the front cover (see illustration). The TDC position
for the camshafts and the auxiliary shaft is set using the timing marks
on the sprocket gears and the markings on the housing.

TDC markings
1 = TDC position of cylinder "1"
2 = Ignition timinig (16° BTDC)