Six-cylinder engine
Drain coolant (section 5.1.1).
Remove radiator (section 5.2.2).
Remove fan with clutch.
Loosen the tension of the belts and unscrew the bolts securing the pulley, keeping the pulley from turning, as shown in fig. 111.
Pic. 111. Removing the pulley of the six-cylinder engine coolant pump. A screwdriver is placed between the heads of the two mounting bolts.
Remove the damper by unscrewing the six mounting bolts with an internal hexagon.
Loosen the mounting bolts and remove the coolant pump. Clean the split surface on the cylinder block.
When reusing the pump, thoroughly clean the split surface. Install a new gasket and a new O-ring. Install the pump in reverse order. Tension the alternator drive belts and coolant pump as described below.
Eight-cylinder engine
Pumps of both types of engines have changed over time, without changing the principle of their operation. On fig. 112 shows the coolant pump of an eight-cylinder engine.
Pic. 112. Coolant pump and engine thermostat M 116/117.
1 - housing cover,
2 - sealing ring,
3 - thermostat.
Drain coolant. Loosen coolant pump drive belts and power steering pump.
Loosen the clamps and remove the coolant hose from the pump.
Remove the spring clips securing the fan shroud, lift the shroud and lead it onto the fan.
Remove the ignition distributor.
In engines of early releases, unscrew the studs of the ignition distributor (with two nuts).
If the temperature gauge sensor is screwed into the inlet pipe, disconnect the wire, also disconnect the wires from the switch of the electromagnetic fan clutch. Remove the front hose clamp, unscrew the mounting bolts and remove the inlet pipe with gasket and spacer.
Remove damper.
On fig. 113 the arrows show the mounting bolts, unscrew the bolts and remove the coolant pump. Thoroughly clean the split surfaces of the pump and cylinder block and install the pump in reverse order. Check ignition timing and adjust if necessary. Tighten the viscous fan clutch bolts to 25 Nm.
Pic. 113. The arrows show the bolts of the eight-cylinder engine coolant pump.
If the pump is damaged, it must be replaced as an assembly. To replace the pump seal, you need an eight-cylinder impeller puller and a six-cylinder impeller press. To perform this work, it is better to contact a service station.