Skoda Felicia

since 1994 release

Repair and operation of the car

Scheme of the GRM drive

Block of cylinders

The block of cylinders is cast from cast iron. The general view and an order of installation of components of the block of cylinders are presented on an accompanying illustration. Directly in a body of the block cylinders are pierced. In the lower part of the block five beds of radical bearings of a bent shaft are executed. Covers of bearings fasten to the block special bolts of M10x65. Washers under heads of bolts are not established.

The axial side play of a bent shaft is controlled by the persistent half rings established on the third radical bearing.

Bent shaft

The bent shaft is forged from steel and consists of five radical and four conrod necks. On a forward pin of a shaft the gear wheel of the drive of the oil pump is fixed and the groove under installation of a segment spline under landing of a cogwheel of a belt of the GRM drive is provided. At a back end face of a shaft the flange under installation of a flywheel is equipped.

Conrod and piston group

Shod rods have the double-T section and a direct section of the lower head. In the top head the bronze plug which then is pierced to the required diameter (17.6 mm) is pressed. The lower head is cut in the middle, and then pierced to diameter 50.6+0.01 (without inserts). The correct mutual provision of a cover of a rod and inserts of the conrod bearing is designated by special tags. Besides, on a head also number of the cylinder to which there corresponds this rod is beaten out. The cover of the conrod bearing fastens to the lower head bolts of M8x1 of the TORX type. In the course of performance of capital repairs it is accepted to make replacement of bolts of covers of conrod bearings. Components of conrod and piston assembly are presented on an illustration.

Pistons are cast from aluminum alloy and have the concave bottom which cavity partly forms combustion chamber volume. At installation the piston has to be deployed by a tag on the bottom towards a GRM drive arrangement. The piston finger having floating landing is fixed in assembly by two lock rings. When landing to a rod the piston is warmed to 60 °C then in it the piston finger refuels. On each of pistons are established on two compression and on one oil scraper ring.

Head of cylinders and gas-distributing mechanism

In a head of cylinders the valves having a line arrangement are placed. The scheme of an arrangement in a head of components of the valvate mechanism is shown on an illustration.

The head of cylinders fastens to the block ten special bolts of M11x1.5 of the TORX type. Sealing laying of a head has a metal fringing of openings under cylinders, and on perimeter is covered with the silicone condensing layer. The correct provision of laying on the block is provided with two adjusting pins put in the interfaced surface of the block of cylinders.

The order of tightening of bolts of fastening of a head of cylinders is shown on an illustration.

Inlet and final channels are removed on different sides of a head. In a body of a head saddles and the directing plugs of valves are pressed, and also camshaft support are created. Covers of bearings of the camshaft fasten in a head M7 bolts. In cases of extreme bearings epiploons are put.

The drive of valves is made directly from the camshaft through the pushers equipped hydraulic with compensators. Hydrocompensators provide the bezzazorny drive of valves. The scheme of functioning of a hydraulic pusher is submitted on an illustration.

The cogwheel of the GRM drive fastens to the camshaft a bolt of M14x1.5x47. The GRM drive is carried out by the belt drive on the basis of a gear CR Power 137STD8-19 belt. The effort of a tension of a belt is provided with the tension roller which is at the same time increasing a corner of coverage of pulleys. At installation of a gear belt it is necessary to achieve combination of adjusting tags. After installation of a belt it is necessary to turn a bent shaft on several turns and again to check correctness of combination of tags.

The effort of a tension of a belt is regulated automatically by means of a hydraulic natyazhitel. The scheme of the GRM drive is submitted on an illustration.

Water pump

The non-demountable centrifugal water pump fastens to the block of cylinders two bolts of M8. Connection is pressurized by a rubber sealing ring. The pump is put in action by a gear gas-distributing belt. In case of refusal replacement of the pump assembled is made.

Inlet pipeline and final collector

The inlet pipeline is manufactured of plastic and divided into four channels connecting to inlet openings of a head of cylinders. The place of a joint is pressurized by a sealing ring. In the inlet pipeline the flowmeter and sensors of temperature of the soaked-up air, and also the air thermostat are placed. Outside the tube of system of catching of fuel evaporations is connected to the pipeline.

The final collector is put on hairpins and fastens to the block by means of M8 nuts. Between a collector and a head it is established the sealing laying reinforced by metal. At installation of a final collector on the engine replacement of laying and fixing nuts is made without fail.