Remove the engine cooling pump for replacement or repair
Usually the pump is removed for replacement, but there are enthusiasts who repair the pumps
Drain the engine cooling system.
Remove the radiator.
Remove the alternator drive belt.
Removing the pump on the ZMZ-4062 engine
1. Unscrew the three bolts 1, holding the pump shaft from turning with a screwdriver 2, and remove the deflector 3 and the water pump pulley 4.
Unscrew fitting 3 and disconnect tube 4 from the pump.
Remove bolt 1 for fastening the pump, loosen clamps 2.
Disconnect the outlet hose 1 of the radiator from the pump by loosening the clamp 2.
Remove the mounting bolts 1 and remove the water pump 2 and the water pump gasket
Removing the pump on the ZMZ-402 engine
1. Remove four screws 1 and remove fan 2 and fan pulley 3.
2. Disconnect hose 2 for draining fluid from the heater from the water pump by loosening clamp 1.
Disconnect the hose 3 from the pump by loosening the clamp 4.
3. Loosen nuts 1 of fastening and remove pump 2 with pump gasket.
Disassembly of the coolant pump
Pumps mounted on motors mod. 4062 and 402 are similar in design.
This shows the disassembly of the motor pump mod. 4062.
For motor pump mod. 402, you must first unscrew the two bolts and remove the pump cover with gasket.
Next, the procedure for disassembling both pumps is the same.
1. Remove pump impeller 1 with a puller.
The impeller is molded from plastic, but has a metal hub, in which a thread for a puller is cut.
2. Press 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
3. Press out seal 1 pump.
4. Rinse and clean the pump parts from deposits.
Inspection of the engine cooling system pump
1. The bearing on the pump shaft must rotate freely, without jamming, 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.
- 2. Examine the impeller. If it has cracks, chips, etc., replace it.
- 3. Examine the seal. If it has tears, cracks, the rubber has lost its elasticity, the compression spring is broken, replace the oil seal.
Engine cooling pump assembly
Pressing on the pulley hub and water pump impeller
- A = (117.5 ± 0.2) mm (motors mone. 402 and 4021);
- B = 0 / 0.2 mm (motors mod. 402 and 4021);
- C = 0.9 / 1.3 mm (motor mod. 4062)
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, it is necessary to punch 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.
