Removal and flaw detection of the gear and the drive shaft of the oil pump VAZ-2123

We conventionally remove the oil pump drive gear and shaft on the engine removed from the vehicle.

To remove the oil pump drive gear, we unscrew the alternator mounting bracket (article – engine dismantling).

Removal of the oil pump drive gear

1. Gripping the rib of the oil pump drive gear retainer with pliers, we extract the retainer from its seat in the cylinder block.

The joint is sealed by a rubber ring fitted on the retainer head.

2. We insert a wooden taper drift with an interference fit into the splined bore of the oil pump drive gear and extract the gear from the cylinder block, turning it anticlockwise.

When fitting the gear, we slip it onto the splined end of the oil pump shaft and engage it with the oil pump drive shaft gear; holding the gear with a screwdriver, we withdraw the wooden drift.

Removal of the oil pump drive shaft

To extract the oil pump drive shaft, the following must be removed:

• the auxiliary drive pulley;
• the timing drive cover;
• the timing drive chain.

1. We extract the oil pump drive gear from the cylinder block.
2. We remove the oil pump drive sprocket. To do this:
   • with a chisel or screwdriver, we bend back the lock washer of the sprocket mounting bolt;

• with a 17 mm spanner, we unscrew the sprocket mounting bolt. We hold the sprocket from turning with a screwdriver which, through the hole in the sprocket, rests on the head of the bolt securing the shaft thrust flange.

• we extract the bolt with the washers.

• we remove the sprocket.

3. Using a 10 mm socket, we unscrew the two bolts securing the shaft thrust flange to the cylinder block and remove the thrust flange.

4. We extract the oil pump drive shaft from the cylinder block seat.

Inspection of the oil pump drive shaft and gear

On the surfaces of the shaft support journals and on the working surface of the eccentric there must be no dents or scores. On the teeth of the oil pump drive and ignition distributor gears, chipping is not permitted; with such a defect, replace the gears and the shaft with new ones.

Oil pump drive shaft bushes

Check the internal diameter of the bushes, their press fit in the seats, and also the alignment of the lubrication hole in the front bush with the channel in the cylinder block (turning of the bush). The inner surface must be smooth and free from scoring.

Having measured the diameters of the shaft and the bushes, determine the clearances between the bushes and the shaft support surfaces. If the clearance exceeds 0.15 mm (limit wear), and also if the surfaces of the bushes are damaged or their press fit is loosened, replace the bushes with new ones.

When replacing, use, both for removal and for fitting, drift А.60333/1/2, observing the following:

• the bushes must be pressed into the seats, and the oil hole in the front bush must be opposite the channel in the cylinder block;

• after pressing in, the bushes must be finally machined and finished to the internal diameter (the dimensions are given in Figure 12).

To ensure full coaxiality of the shaft bushes, reamer А.90353 is used for their finishing, with which both bushes are machined simultaneously.

Oil pump drive gear bush

Check the press fit of the bush. The inner surface must be smooth and free from scoring, otherwise replace the bush.

To press out and press in the bush, use drift А.60З26/I. After pressing in, machine the bush with a reamer to 16.016-16.037 mm.

Installation

1. We fit the oil pump drive shaft in the reverse order.
2. We carry out the further reassembly in the reverse order.
3. We replace the torn or perished rubber ring of the retainer with a new one.