Removal and installation the timing belt (BMW 3 Series E30)

Caution: The removed toothed belt cannot be reinstalled, and if it has simply become loose, it must be replaced regardless of the mileage.

Removal

Remove the engine compartment hood (see section "Removal and installation the engine compartment hood").

Remove the air filter (see section "Removal and installation the air filter").



Using a screwdriver, pry up the left and right expansion rivets, having first knocked out the expansion pins.

Pull the fan casing upward.

Remove all spark plug tips. To facilitate removal, use the HAZET 1849 puller.



Remove the distributor cover "1". To do this, lift the left and right clamping strips with a screwdriver.

Move cable channel "2" upwards. To do this, insert a screwdriver into the slots (arrow).





Unscrew the ignition distributor cap and remove it together with the ignition wires. This requires an 8 mm bent wrench.

Unscrew the distributor runner "4" and remove the trim ring "3".



Remove the V-belt from the generator. To do this, unscrew bolt "1" and the nuts of bolts "2" and "3". Turn bolt "3" in the direction of the arrow and thereby loosen the tension of the V-belt.

Loosen the water pump pulley. At the same time, tighten the V-belt to prevent the pulley from turning.

Unscrew the vibration damper from the crankshaft. At the same time, engage 1st gear, tighten the handbrake to hold the pulley from turning.

Drain the coolant (see section "Replacing the coolant").

Unscrew the thermostat housing under the ignition distributor and set it aside. Remove the thermostat.



Unscrew the 5 bolts securing the lower timing belt cover. Remove the cover.

Unscrew the 4 bolts securing the upper timing belt casing. Do not lose the centering bushings of the upper bolts.

Set cylinder 1 to the top dead center position (see section "Removal and installation the ignition distributor").



Lock the crankshaft in the top dead center position with the appropriate rod. To do this, insert the rod through the hole (arrow) in the engine block into the hole in the flywheel.



Loosen the camshaft drive sprocket mounting bolt without unscrewing it. This requires a Torx key head.



Loosen the tension roller nut "2". Move the tension roller inward, relieving the toothed belt. Parts shown in the figure: 1 - toothed pulley of the camshaft; 3 - idler pulley; 5 - oil pump; 6 - oil pressure regulating valve; 7 — timing case cover.



Remove the timing belt.

Caution: When the timing belt is removed, do not change the position of the engine if possible.

Installation

Caution: When applying the timing belt, the position of neither the camshaft, nor the intermediate shaft, nor the crankshaft should change. Otherwise, serious damage to the engine may occur or it will not develop full power. After tensioning the timing belt, check the installation of the camshaft and crankshaft again.

Unscrew the cylinder head cover, pull out the camshaft cover.

Check the camshaft position at top dead center. At the service station, the camshaft is locked at top dead center using the BMW 1131190 device. The camshaft is at top dead center when the cams of the 4th cylinder intersect. The intersection of the cams is their position, in which they are symmetrically facing left and right relative to the inclined engine.

Slightly (tightening torque 1-3 Nm) tighten the camshaft toothed pulley bolt. Turn the toothed pulley in the direction of engine rotation until it stops, with the protrusion entering the recess.

Tighten the tension roller nut slightly so that it can still be moved.

Place the toothed belt with tension from the toothed pulley of the crankshaft on the tension roller.

Center the timing belt on the camshaft toothed pulley.

Set the scale of the timing belt tension measuring device to 0.

Place the measuring device between the tension roller and the toothed pulley of the camshaft so that both outer rollers of the device are adjacent to the back of the toothed belt.



Turn the tension roller to the left with the Allen key, thus tensioning the toothed belt. Specified value when measured with BMW 112080: 32±2 scale divisions.

Tighten the tension roller to a torque of 22 Nm.

Tighten the camshaft timing pulley to a torque of 60±5 Nm.

Install the camshaft cover and cylinder head cover.

Caution: Pull out the engine lock rod.

Screw on the upper timing belt cover, ensuring that the bushings are securely seated.

Screw on the lower timing belt cover, after checking and replacing the gasket if necessary.

Insert the thermostat into its housing. Check the integrity of the sealing ring and replace it if necessary.

Screw on the thermostat housing.

Fill the cooling system with coolant, remove air from the cooling system (see section "Replacing the coolant").

Place the vibration damper on the crankshaft, aligning the hole in the vibration damper exactly with the centering pin. Tighten the vibration damper fastening with a torque of 23 Nm.

Screw on the water pump pulley, holding the pulley with a V-belt to prevent it from turning.

Apply and tension the V-belt (see section "Removal and installation the alternator V-belt. Replacing the V-belt").

Tighten nuts and bolts 1-3 in Figure W-1056.

Insert the camshaft sprocket cover, checking the integrity of the O-ring and, if necessary, replacing the ring.

Screw on the distributor rotor.

Screw on the distributor cap.

Insert the ignition wires into the insulator guides.

Insert the cable channel into the cylinder head cover.

Put on the spark plug caps.



Insert the fan casing with the left and right strips into the holders. Insert the spacer rivets from the top left and right and drive the plastic cores into them.

Install the air filter (see section "Removal and installation the air filter").

Install the engine compartment hood (see section "Removal and installation the engine compartment hood").

Caution: If the adjusting and measuring tool is missing (abroad, in case of an accident on the road), temporarily tighten the toothed belt so that the belt can deflect by 5-10 mm between the tension roller and the toothed pulley of the camshaft. The belt tension should be checked at the earliest opportunity using a measuring device. Until then, avoid high engine speeds.