Possible malfunctions of the pump (Fig. 1) can be: fluid leakage through the impeller stuffing box as a result of wear of the sealing washer or destruction of the rubber cuff of the stuffing box, bearing wear, impeller breaks and cracks

UAZ engine cooling pump

Fig. 1. Usengine cooling system

Repair of pump 21–1307010–52 of the cooling system

Remove fluid leakage from the pump by replacing the sealing washer and rubber cuff.

To replace, remove the pump from the engine, disconnect it from the bracket, remove the impeller with tool 71-1769 (Fig. 2), remove the sealing washer and the stuffing box collar.

To assemble the impeller stuffing box, insert into the stuffing box holder located on the pump casing, first the rubber seal assembly, and then the sealing washer and the retaining ring.

At the same time, grease the part of the pump shaft mated with the rubber cuff before installing the stuffing box and pressing the impeller with soap, and the end of the impeller in contact with the sealing washer with a thin layer of graphite grease.

Before installing the gland, check its end (the end of the sealing washer) for paint: when the gland is compressed to a height of 13 mm, the end print must have at least two completely closed circles without breaks.

Press the impeller onto the roller on a hand press until its hub stops against the end of the flat.

In this case, the pump should be supported by the front end of the roller on the table, and the force should be applied to the impeller hub.

To replace the bearings or the pump shaft, disassemble the pump completely in the following order:

Removing the pump impeller

Fig. 2. Removing the pump impeller

1. Remove the impeller from the pump shaft and remove the sealing washer and rubber cuff.

Removing the pump pulley hub

Fig. 3. Removing the pump pulley hub

2. Loosen the pulley hub mounting nut and remove it using the tool as shown in Fig. 3.

Pump roll out

Fig. 4. Pressing out the pump shaft: 1 - pump casing; 2 - roller; 3 - stand 3.

Remove the retaining ring of the bearings from the housing 1 (Fig. 4) of the pump and use a press to press out or knock out the roller 2 with the bearings from the housing with a copper hammer, resting the front end of the housing on the stand 3 with a hole for the passage of the bearings.

Pressing the roller together with the bearing into the pump casing</ p>

Fig. 5. Pressing the roller together with the bearing into the pump housing: 1 - roller; 2 - pump housing; 3 - mandrel; 4 - stand

Assemble the pump in reverse order. At the same time, press the new bearing onto the roller 1 (Fig. 5) and into the housing 2 at the same time using a manual press and a mandrel

3. The felt seal of the bearing must face towards the circlip.

Putting the spacer on the roller, press the second bearing with the felt seal outward.

After installing the retaining ring, press the pulley hub onto the front end of the roller, resting the roller against the rear end of the ring.

Press the pulley hub onto the pump shaft of the model 4218 engine after installing the latch 19 (see Fig. 1, b).

When pressing on the hub, make sure there is no gap between the bearing and the circlip.

After assembling the pump, fill the housing cavity between the bearings with grease according to the instructions in the lubrication table.

When installing the assembled pump on the engine, pay attention to the suitability of the paronite gasket between the casing and the pump bracket.

Repair of pump 421-1307010-01 of the cooling system

Remove fluid leakage from the pump by replacing the stuffing box 21 (see Fig. 1, b) as an assembly.

If the roller-ball bearing 19 is worn out, replace it as an assembly with the roller.

To replace the stuffing box or shaft assembly with bearing, remove the pump from the engine, disconnect it from the cover, remove the impeller with tool 71–1769 (see Fig. 2).

Using the tool (see fig. 3), remove the fan pulley hub and press out the roller with the bearing.

Before pressing the bearingbe sure to unscrew the latch 20 (see Fig. 1, b).

Press out the oil seal.

Assemble the pump in reverse order. At the same time, press the hub of the fan pulley all the way into the collar, and press the impeller up to the size 117.4 +0.925 –1.035 (see Fig. 1, b).

Before assembling, lubricate the part of the shaft of the roller-ball bearing associated with the oil seal with soap, and the end of the impeller that comes into contact with the oil seal with graphite grease.

When installing the assembled pump on the engine, pay attention to the suitability of the paronite gasket between the cover and the pump housing.