Removing accessory drive belts and tensioners

In order to remove the alternator, fan and A/C compressor belts, do the following (see Fig. 1):

  • 1. Using a wrench, press the tensioners in the direction shown in Fig. 1.

There are holes on the movable and fixed parts of the tensioner, when combined, it can be fixed in the wrung out state.

  • 2. Remove the belts (650.1308020 - fan drive belt; 650.3701032 - generator drive belt; air conditioning compressor drive belt is installed by the consumer).

Removing and installing drive belts and tensioners YaMZ-650

  • 3. Loosen the tensioner bolts (1, 4, 5).
  • 4. Remove tensioners (650.1308110 - fan drive belt tensioner, 650.3701715 - alternator drive belt tensioner, 650.8114110 - air conditioning compressor drive belt tensioner).
  • 5. Loosen the intermediate roller bolt (6).
  • 6. Remove intermediate roller with bearing assembly (3) (650.1308111).
  • 7. Remove the intermediate roller bracket (650.1308139) by unscrewing the mounting bolts (2).

Installing accessory drive belts and tensioners

Install the drive belts of the units and tensioners in the reverse order of removal.

When installing the fan belt tensioner, the threads of the bolt (5) must be sealed with Loctite 542 sealant.

Tighten the bolts for fastening the tensioners of the fan and generator drive belts to a torque of Mcr = 40 ± 8 Nm.

Tighten the intermediate roller mounting bolt with a torque of Mcr = 60 ± 12 Nm.

The belt tension adjustment value is obtained automatically by the tensioning system.

If, upon external examination, the belt shows wear on the side faces, delamination of the belt, or the presence of cracks and breaks along the compression layer, then the belt must be replaced.

When carrying out repairs, avoid getting oil, fuel, coolant and paint on the belts.