Drive Belts, Mounts, Brackets and Accessories: Description and Operation

Accessory Drive

Crankshaft Pulley
The combined crankshaft pulley and torsional vibration damper drives a single, seven ribbed vee belt. The belt drives all of the engine-mounted accessories; the generator, the power assisted steering pump, the air-conditioning compressor and the coolant water pump.

Idler Pulley
An idler pulley, on the right-hand accessory mounting, increases the wrap-angle around the generator pulley.

Coolant Pump Drive
The coolant pump pulley is the uppermost of the accessory drive pulleys. The coolant pump is fitted between the two cylinder banks on the front face of the engine.

Air Conditioning Compressor Drive
This is positioned at the lowest point of the front-end accessory-drive on the left hand side accessory mounting.

Power Assisted Steering Pump Drive
The power assisted steering pump pulley is located on the left side, above the air-conditioning compressor.

Generator Drive
The generator is fitted on the right hand accessory mounting.

Drive Belt





The drive belt should be inspected at every routine service for excessive wear and damage. A drive belt, which displays symptoms of cracking, may be perfectly fit for further service.
Should cracking be detected, serviceability may be assessed using the following guidelines:
Fifteen cracks per rib over a 100 mm length of drive belt is acceptable.
Section(s) of belt missing from any rib is not acceptable and the drive belt must be renewed.

Automatic Belt Tensioner








The automatic belt tensioner consists of an idler pulley, which is free to rotate on a bearing, located at the end of a spring-loaded pivot arm.
The pivot arm can be turned counter-clockwise (viewed from the front of the engine) for belt removal and installation.
A belt-wear indicator is incorporated on the rear horizontal face of the pivot arm.

Accessory Mounting Brackets





All engine accessories are rigidly-mounted onto the cylinder block by means of accessory mounting brackets on the left and right-hand sides of the engine.
The left-hand bracket supports the air-conditioning compressor and steering pump.
The right-hand bracket supports the generator.
Dowels between the accessory mounting brackets and the engine ensure that the accessory pulleys are accurately aligned with the accessory drive belt.

Accessory Drive on Supercharged Engines
The front end accessory drive description and information for the supercharged engine is identical to that given above. The only difference is that the drive belt for the supercharger passes immediately in front of the accessory drive belt. Therefore, before any work can be done on the accessory drive belt and associated components, the supercharger drive belt must first be removed.