BMW E36 – Head and timing gear
Removing and installing the toothed belt
BMW 316i versions, 318i do VIII 1993
Caution. A used toothed belt cannot be put back on. If it was loose and disassembled, a new belt must be fitted, regardless of the degree of wear. A special BMW tool is required to adjust the belt tension.
• Remove the fan.
• Remove all spark plug caps. Hazet tongs can be used 1849.
• Remove the ignition distributor cover (1, Lynx. W-1054). To do this, lever it off at the bottom and at the top with a screwdriver, to release the tabs.
• Pry the cable tunnel upwards (2), pressing the tip of the screwdriver into the slots marked with the black arrow.
• Unscrew the three screws securing the ignition distributor cap and remove it together with the high-voltage cables.
• Unscrew and remove the distributor finger (4, Lynx. W-1055) together with the cover (3).
• Remove the V-belt from the alternator. To do this, loosen the screw (1, Lynx. W-1056) and unscrew the nuts of the bolts (2) i (3). Turn the screw (3) in the direction of the arrow and release the V-belt.
• Loosen the coolant pump pulley. Squeezing the belt will allow you to hold the wheel.
• Turn on 1. run, apply the emergency brake, to block the pulley, and unscrew the torsional vibration damper from the crankshaft (1, Lynx. W-10106). The remaining elements are shown in the picture: 2 – pulley, 3 – hexagonal bolt, 4 – guide washer, 5 – central screw, 6 – toothed belt pulley, 7 – a locating pin, 8 – spring washer, 9 – V-belt.
• Drain the coolant (see article "Maintenance").
• Unscrew the three screws under the manifold (10, Lynx. W-10176), mounting the cooling system thermostat housing, take out the thermostat (6) together with the gasket (7).
• Remove the five screws (14, Lynx. W-10177) fasteners on the lower toothed belt cover and remove the cover with the gasket.
• Remove the four screws (20) upper toothed belt cover and remove the cover. Be careful, so as not to lose the fitted sleeves (16) top mounting bolts.
• Position the plunger 1. cylinder at TDC; the ignition distributor finger on the camshaft pulley should face downward. Check the TDC setting on the camshaft, as described under "Installing the belt".
• Lock the crankshaft at TDC position using a suitable pin. To do this, insert the pin through the hole in the engine block (the arrow in fig. W-1057) into the hole in the handwheel.
• Loosen the bolt securing the camshaft sprocket, without twisting it. You need a Torx key for this.
• Loosen the nut on the tensioner wheel (2, Lynx. W-1059). Turn the roller inward to release the toothed belt. The remaining elements are shown in the picture: 1 – camshaft drive pulley, 3 – return roller, 4 – coolant pump, 5 – oil pump, 6 – oil pressure regulating valve, 7 – timing cover.
• Remove the toothed belt.
Caution. After removing the toothed belt, leave the crankshaft at TDC position.
Caution. When installing the toothed belt, it is necessary to set the crankshafts and timing to the TDC position. Failure to do so may seriously damage the engine or the engine will not develop full power.
• Unscrew the cylinder head cover, remove the camshaft cover.
• Check the camshaft alignment at TDC. In the workshop, a BMW tool is used to set the camshaft at TDC 1131190. The camshaft is at TDC then, when the cams for 1. the cylinders are oriented symmetrically upwards to the right and left in relation to the upper edge of the cylinder head, taking into account the oblique position of the motor.
• Slightly tighten the camshaft drive pulley bolt to torque 1 – 3 Nm. Turn the wheel as far as it will go in the direction of crankshaft rotation, so that the protrusion fits into the groove.
• Tighten the tensioner pulley nut slightly so, so that the roller can be turned.
• Starting with the crankshaft pulley, position the belt on the camshaft pulley, then onto the tensioner roller. Caution. The toothed belt must be correctly positioned on all pulleys.
• Set the toothed belt tension gauge to "0".
• Place a gauge between the crankshaft gear and the camshaft gear yes, so that both outer rollers rest against the back of the toothed belt, and the center pin engages the tooth gap of the belt. Follow the instructions for use of the device. Caution. The engine should be at room temperature (ok. 20°C).
• Turn the tensioner roller counterclockwise with the Allen key, tightening the toothed belt until it is tightened, until the measuring instrument BMW-112080 shows 45-50 scale plots.
• Tighten the tensioner roller to the torque 22 Nm.
• Tighten the camshaft pulley to the torque 60 ± 5 Nm.
Caution. Remove the crankshaft locking pin, a camshaft positioning tool and a timing device for tensioning the toothed belt.
• Grasping the central bolt securing the crankshaft pulley with a wrench, make at least two rotations of the shaft in the direction of its rotation.
• Place the crankshafts and camshafts in their TDC position (as described).
• Loosen the camshaft pulley fastening bolt again.
• Mount the measuring device BMW-112080.
• Loosen the tensioner roller bolts and briefly tension the toothed belt to its value 45-50 scale plots.
• Finally set the tensioner roller to the position on the instrument 32 ± 5 scale plots.
• Tighten the tensioner roller to the torque 22 Nm.
• Tighten the camshaft pulley to the torque 60 ± 5 N m.
Caution. Remove the crankshaft locking pin and the camshaft positioning tool and the toothed belt tension gauge.
• After adjusting the toothed belt tension, it is recommended to re-check the alignment of the crankshafts and timing.
• Install the camshaft cover and install the cylinder head cover.
• Screw on the upper toothed belt cover, paying attention to the correct seating of the fitted bushings.
• Check the condition of the rubber seal, replace the gasket if necessary.
• Screw on the lower toothed belt cover.
• Put the thermostat into the housing. Check the condition of the sealing ring, replace it if necessary.
• Clean contact surfaces, fit a new gasket and screw on the thermostat housing.
• Fill with liquid and bleed the cooling system.
• Place the torsional vibration damper on the crankshaft, by aligning the calibrated hole of the muffler with a fitted pin. Tighten the torsional vibration damper to the torque 23 Nm.
• Tighten the coolant pump pulley, holding the pulley by the V-belt.
• Fit and tension the V-belt.
• Tighten bolts and nuts (1) do (3) shown in Figure W-1056.
• Install the camshaft pulley cover. Check the condition of the cover sealing ring and replace it if necessary.
• Install the finger and ignition distributor cap in the reverse order of the removal steps.
• Place the high-voltage cables in the guides of the insulating element.
• Press the cable tunnel into the cylinder head cover.
• Install the spark plug caps in the order of firing the cylinders: 1 -3-4-2.
• Place the fan guard at the bottom on the hooks on the left and right. Insert at the top, on the left and right, plastic expansion pins and wedge with impacts.
• Install the fan.
Caution. If you do not have a measuring instrument (e.g.. crash while traveling), the toothed belt should be temporarily tightened like this, so that you can bend it with your thumb approx. 5 do 10 mm between the camshaft pulley and the tensioner roller. If this is the case, check the belt tension using the tool and avoid high engine rpm in the meantime.