Usually, the coolant pump is removed from the engine due to noise during its operation, excessive radial play of the pump shaft
Conditionally, all operations are carried out on a removed engine.
Removing the coolant pump from the engine
To remove the pump, loosen and remove the pump drive belt.
Holding the pump pulley with a “gas” key, with a “12” key, unscrew the four bolts securing the pulley.
You can still hold the pulley with a mounting spatula, inserting it into the gap between the two bolts.
Remove the pulley and plate
If a fan is attached to the pump hub, then unscrew the bolts, holding the fan blades.
Using the “13” head, we unscrew the five nuts securing the pump to the cylinder block.
Remove the coolant pump
Remove the gasket by carefully prying it with a knife
Using a key or a “10” head, unscrew the bolt securing the pump cover
Carefully tapping with a copper hammer, remove the pump cover
Remove the gasket
Disassembly of the coolant pump
For motor pump mod. 402, you must first unscrew the two bolts and remove the pump cover with gasket.
Remove pump impeller 1 using a puller.
The impeller is molded from plastic, but has a metal hub, in which a thread for a puller is cut.
Compress the hub 1 of the pump pulley with a puller.
Unscrew retainer 2 of the bearing and press the bearing with the pump shaft towards the pulley
Push out seal 1 pump
Rinse and clean the pump parts from deposits
Coolant pump troubleshooting
The bearing on the pump shaft must rotate freely without binding, otherwise replace the bearing with shaft assembly.
If a large play is felt in the bearing, traces of lubricant leakage from under the protective rings are noticeable or the balls roll when the bearing rotates, it must be replaced as an assembly with the roller.
Inspect the impeller.
If it has cracks, chips, etc., replace it.
Inspect the gland.
If it has tears, cracks, the rubber has lost its elasticity, the compression spring is broken, replace the oil seal.
Pump Assembly
The pump is assembled in the reverse order of disassembly.
When assembling the pump, inspect the gaskets, if they have tears or the gaskets are heavily compressed, they must be replaced.
When pressing the impeller and hub, the emphasis should be on the pump shaft.
When assembling the pump, keep the dimensions shown in the figure.
After screwing in the bearing retainer, you need to punch out the edges of the hole so that part of the metal enters the slot of the retainer to prevent self-loosening.
Installation is carried out in the reverse order of removal.
Tightening torques for parts:
- Water pump pulley bolts 22-27 Nm (2.2-2.7 kgf.m)
- Water pump mounting bolts 22-27 Nm (2.2-2.7 kgf.m)