Water pump repair

To remove and disassemble the water pump:

  • - drain the coolant from the engine;
  • - remove the water pump drive belts;
  • - unscrew the three bolts of the water pump;
  • - remove the water pump from the water pipes.

Water Pump Repair

Disassemble the pump in the following order:

  • - bend the lock washer 16 (see Fig. Water pump) and, holding the roller from turning the pulley, unscrew the cap nut 17;
  • - remove the impeller 14 with a puller;
  • - remove the sealing rubber ring 12 with the clip and the thrust ring 10;
  • - remove gland 9;
  • - unscrew the bolt 1 , remove the washer;
  • - remove pulley 3 with a puller;
  • - remove the key and dust deflector 4;
  • - remove retaining ring 5;
  • - remove roller 15 complete with bearings;
  • - remove cuff 8.

When assembling, do not allow foreign particles to get between the surfaces of the rubbing pair of the mechanical seal.

After assembly, check the ease of rotation of the pump roller (no sticking is allowed).

When repairing a water radiator the defects of the radiator include damage to tanks and tubes, poor soldering of parts, as well as external contamination and significant scale deposits in the tubes.

Rinse the contaminated core of the radiator from the outside in the direction opposite to the air flow.

Check the tightness of the radiator, for which close the openings of the pipes with plugs, and supply compressed air at a pressure of 78.51 kPa (0.8 kgf / cm2) to one of them, while the radiator must be filled with coolant.

The tightening torque of the fan hub nut is 137.3-196.2 Nm (14-20 kgf-m).

Part dimensions and allowable wear, mm

Water pump

Rated / Allowed

Diameter of the hole in the water pump housing:

  • - for front bearing 61.99-62.02 / 62.04
  • - for rear bearing 51.99-52.02 / 52.04
  • - for stuffing box 36.45-36.474 / 36.474

Water pump shaft neck diameter:

  • - for front bearing 25.002-25.017 / 25
  • - for rear bearing 20.002-20.017 / 20
  • - for impeller 15.64-15.675 / 15.64

Diameter of the hole in the impeller for the shaft neck 15.60-15.635 / 15.62

Diameter of pulley hole for roller neck 24.90-24.923 / 24.94

Fan drive fluid coupling

Rated / Allowed

Drive shaft:

  • - bearing journal diameter34.973-34.99 / 34.96
  • - rear bearing hole diameter 47.010-47.035 / 47.00

Output journal diameter:

  • for front bearing 24.993-25.007 / 24.986
  • for rear bearing 20.002-20.017 / 19.995

Bearing bore diameter in bearing housing 71.970-72.0 / 72.015

Generator drive pulley shaft:

  • - bearing hole diameter 61.970-62.0 / 62.015
  • - bearing neck diameter 70.01-70.03 / 70
  • - diameter of the neck under the cuff 99.930-100.0 / 99.3

To remove and disassemble the fluid coupling:

  • - drain the oil from the engine;
  • - remove the water pump drive belts and fan impeller, centrifugal oil filter, oil crankcase;
  • - unscrew the bolts securing the front cover to the cylinder block and remove the fluid coupling assembly with the front cover of the block;
  • - straighten the mustache of the lock washer of the fan hub fastening nut, unscrew the nut and remove the hub:

  • - unscrew the pulley mounting bolts, remove the pulley 1 (see Fig. Fan drive fluid coupling) with the cuff 4 as an assembly and sleeve 3 of the cuff;
  • - remove the bearing retaining ring;
  • - unscrew the screws securing the bearing housing, remove the housing 13 complete with the bearing;
  • - remove the fluid coupling from the front cover of the block;
  • - unscrew the bolts securing the drive shaft assembly with the casing to the drive wheel, remove the drive shaft 17 with the casing assembly;
  • - remove the driven shaft 18 complete with the driven wheel.

After assembly, the generator drive pulley, as well as the driven shaft, with a stationary pulley, should rotate freely, without jamming.

To remove and disassemble the thermostat box:

Removing the thermostat box

  • - unscrew the bolt 1 fastening the generator bar (Fig. Removing the thermostat box):
  • - unscrew two bolts 5 securing the box flange;
  • - unscrew the three bolts 6 securing the box and remove the box;
  • - unscrew the five bolts 2 fastening the branch pipe, remove the branch pipe 3. take out the thermostats and inspect them.

Thermostat Test Scheme

To check thermostats, determine the opening start temperature and valve stroke 5 (see Fig. Thermostat) as follows:

  • - immerse the thermostat in a heated water bath (3 l), the level of which should be above the thermostat flange (see Fig. Installation diagram for checking thermostats).
  • - after reaching a temperature of plus 70 ° C, heat the water constantly with an intensity of no more than 3 ° C / min, stirring. Use a mercury thermometer with a division value of no more than 1 ° C;
  • - check the beginning of the thermostat valve opening with the indicator - this is the temperature at which the valve stroke will be 0.1 mm.

Thermostats should begin to open at 78-82°C and fully open at 91-95°C. The full stroke of the thermostat valve must be at least 8.5 mm.

During operation, the temperature of the beginning of opening is 77-83 °С, full opening - 90 - 96 °С, the loss of valve stroke is not more than 20%.

Fluid clutch switch operation diagram

If the fan switch-on temperature cannot be maintained within the range of 86 - 90 °C, replace the thermal power valve, which consists of a sensor (see Fig. Fluid coupling switch), body and seat.

To remove and disassemble the fluid coupling switch:

  • - unscrew the bolts securing the switch to the inlet pipe, remove the switch;
  • - fix the switch to the body in a vise;
  • - remove the cap, take out the cork, spring and ball
  • - remove the valve assembly with the thermal force sensor.

The valve and plug must move in the body without jamming.

On the mating surface of the housing, do not allow marks deeper than 0.05 mm; surface non-flatness should be no more than 0.05 mm.

There should be no centers of cavitation damage or damage on the surface of the sensor body.